U.S. patent application number 15/701720 was filed with the patent office on 2018-04-19 for method and apparatus for controlled or programmable cutting of multiple nested tubulars.
The applicant listed for this patent is TETRA Applied Technologies, LLC. Invention is credited to Mark F. Alley, Wesley Mark McAfee.
Application Number | 20180106122 15/701720 |
Document ID | / |
Family ID | 46245365 |
Filed Date | 2018-04-19 |
United States Patent
Application |
20180106122 |
Kind Code |
A1 |
McAfee; Wesley Mark ; et
al. |
April 19, 2018 |
Method and Apparatus for Controlled or Programmable Cutting of
Multiple Nested Tubulars
Abstract
A methodology and apparatus for cutting shape(s) or profile(s)
through well tubular(s), or for completely circumferentially
severing through multiple tubulars, including all tubing, pipe,
casing, liners, cement, other material encountered in tubular
annuli. This rigless apparatus utilizes a computer-controlled,
downhole robotic three-axis rotary mill to effectively generate a
shape(s) or profile(s) through, or to completely sever in a 360
degree horizontal plane wells with multiple, nested strings of
tubulars whether the tubulars are concentrically aligned or
eccentrically aligned. This is useful for well abandonment and
decommissioning where complete severance is necessitated and
explosives are prohibited, or in situations requiring a precise
window or other shape to be cut through a single tubular or
plurality of tubulars.
Inventors: |
McAfee; Wesley Mark;
(Montgomery, TX) ; Alley; Mark F.; (The Woodlands,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TETRA Applied Technologies, LLC |
The Woodlands |
TX |
US |
|
|
Family ID: |
46245365 |
Appl. No.: |
15/701720 |
Filed: |
September 12, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14381184 |
Jan 12, 2015 |
9759030 |
|
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PCT/US2011/065148 |
Dec 15, 2011 |
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15701720 |
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61423950 |
Dec 16, 2010 |
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61423961 |
Dec 16, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 44/00 20130101;
E21B 29/005 20130101; E21B 29/00 20130101; E21B 47/09 20130101;
E21B 43/11 20130101 |
International
Class: |
E21B 29/00 20060101
E21B029/00; E21B 47/09 20120101 E21B047/09; E21B 43/11 20060101
E21B043/11 |
Claims
1. A method of programmably severing a plurality of nested
tubulars, each tubular having a tubular bore, the nested tubulars
being disposed in a well bore and wherein there is an outer tubular
and an at least one inner tubular inside the bore of the outer
tubular, the method comprising the steps of: (a) providing a
cutting tool, the cutting tool including: (i) a tool body
configured to be lowered into the tubular bore of the innermost
nested tubular, the tool body having a longitudinal Z-axis, a
W-axis of rotation rotating about the Z-axis, and an anchoring
system attached to the tool body, the anchoring system having
engaged and non-engaged conditions, wherein during the engaged
condition the tool body is anchored relative to the innermost
tubular, and during the non-engaged position the tool body is not
anchored relative to the innermost tubular; (ii) the tool body
including a cutting head movably connected to the tool body in both
the Z and W axes; (iii) the cutting head being coupled to a first
motor drive, wherein the first motor drive causing the cutting head
to be moved in the W-axis of rotation relative to the tool body;
(iv) the cutting head being coupled to a second motor drive,
wherein the second motor drive causing the cutting head to be moved
in the Z-axis relative to the tool body; (v) the cutting head
including: a spindle housing pivotally connected to the cutting
head at a pivot axis allowing pivoting in a Y-axis, the spindle
housing having: (1) an elongated cutting member with distal and
proximal ends, and the elongated cutting member being rotationally
connected to the spindle housing, the elongated cutting member
having a longitudinal axis, the longitudinal axis being
perpendicular to the pivot axis of the spindle housing, (2) a third
motor drive operably connected to the elongated cutting member
causing the elongated cutting member to rotate about the elongated
cutting member's longitudinal axis and relative to the spindle
housing; (3) an arcuate actuator operatively connected to the
spindle housing and elongated cutting member, the actuator causing
the elongated cutting member to move about the Y-axis; and (vi) a
programmable controller operably connected to the cutting tool and
controlling movement of the cutting head or elongated cutting
member in the Z-axis, W-axis, Y-axis, and rotation about the
elongated cutting member's longitudinal axis; (b) from a surface
location lowering the cutting tool into an innermost tubular of a
plurality of nested tubulars; (c) engaging the anchoring system
such that the tool body is anchored relative to the innermost
tubular; (d) the second drive motor extending the cutting head to a
first Z axis cutting position Z1; (e) the third drive motor causing
the elongated cutting member to rotate about the rotational cutting
axis; (f) the actuator causing the elongated cutting member to move
to a first Y-axis arcuate position Y1; (g) while the elongated
cutting member is at the Y1 arcuate angle, the second drive motor
rotating the cutting head in the W-axis at least one complete
revolution; (h) during step "g", the second drive motor causing the
cutting head to retract in the Z axis to a second Z-axis cutting
position Z2, wherein Z2 is less than Z1; (i) after step "h", the
second drive motor extending the cutting head to a third Z axis
cutting position Z3, wherein Z3 is greater than Z2; (j) after step
"h", the actuator causing the elongated cutting member to move to a
second Y-axis arcuate position Y2, wherein Y2 is greater than Y1;
(k) while the elongated cutting member is at the Y2 arcuate angle,
the second drive motor rotating the cutting head in the W-axis at
least one complete revolution; (l) after step "b", and without
raising the tool body to the surface location, completely severing
the plurality of the nested tubulars with the elongated cutting
member; and (m) inputting size information for each of a plurality
of nested tubulars, and based on the inputted size information, the
controller controlling steps "d" through "k".
2. The method of claim 1, wherein during step "m", for any of the
tubulars to be cut, the controller accepts input regarding: a
target Y-axis cutting position of the elongated cutting member
relative to a preselected Y-axis home position.
3. The method of claim 1, wherein during step "m", for any of the
tubulars to be cut, the controller accepts input regarding target
starting and finishing Z-axis cutting positions for the cutting
head (e.g., for the tubular being cut to provide a desired finished
gap or swath or cut), relative to a preselected Z-axis home
position.
4. The method of claim 1, wherein during step "m", for any of the
tubulars to be cut, the controller accepts input regarding the
diameters of the tubulars.
5. The method of claim 1, wherein during step "m", for any of the
tubulars to be cut, the controller accepts input regarding the
thickness of the tubulars.
6. The method of claim 1, wherein during step "m", for any of the
tubulars to be cut, the controller accepts input regarding the
eccentricity or out of roundness of the tubulars.
7. The method of claim 1, wherein during step "m", for any of the
tubulars to be cut, the controller accepts input regarding the
amount of offset of one or the tubulars related to another
tubular.
8. The method of claim 1, wherein the controller is operably
connected to a display, and, based on input regarding the nested
tubulars to be cut, the controller determines and displays on the
display target values for one or more of the nested tubulars to be
cut, and the user can override one or more target values for
movements in Y-axis (e.g., target cutting position for a particular
tubular), Z-axis (e.g., starting and finishing Z-axis locations for
a particular tubular), W-axis (e.g., angular rotational speed),
and/or ECMLAR (e.g., angular rotational speed).
9. The method of claim 1, wherein the controller is operably
connected to a display, and, based on input regarding the nested
tubulars to be cut, the controller displays on the display a
pictorial representation of the cuts which will be made in the
plurality of nested tubulars by the elongated cutting member.
10. The method of claim 9, wherein the pictorial display made on a
tubular by tubular basis.
11. The method of claim 10, wherein an operator is provided an
option to select which of the set of tubulars a pictorial display
will be made.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of U.S. patent application Ser. No.
14/381,184, filed on Jan. 12, 2015 (now U.S. Pat. No. 9,759,030),
which entered the U.S. national stage from PCT patent application
serial number PCT/US2011/065148, with international filing date
Dec. 15, 2011, which claims the benefit of both U.S. provisional
patent application Ser. No. 61/423,950, filed on Dec. 16, 2010, and
U.S. provisional patent application Ser. No. 61/423,961, filed on
Dec. 16, 2010.
[0002] The following applications are incorporated herein by
reference:
[0003] U.S. patent application Ser. No. 14/381,184, filed on Dec.
15, 2011 (now U.S. Pat. No. 9,759,030), entitled "Method and
Apparatus For Programmable Robotic Rotary Mill Cutting Of Multiple
Nested Tubulars"
[0004] PCT patent application serial number PCT/US2011/065148, with
international filing date Dec. 15, 2011 entitled "Method and
Apparatus For Programmable Robotic Rotary Mill Cutting Of Multiple
Nested Tubulars";
[0005] U.S. patent application Ser. No. 12/540,924, filed Aug. 13,
2009;
[0006] U.S. patent application Ser. No. 12/484,211, filed Jun. 14,
2009, entitled "Method and Apparatus For Programmable Robotic
Rotary Mill Cutting Of Multiple Nested Tubulars";
[0007] U.S. provisional patent application Ser. No. 61/131,874,
filed Jun. 14, 2008, entitled "Rotary Milling Casing Cutter."
DESCRIPTION
Field
[0008] The present disclosure generally relates to methods and
apparatus for mill cutting through wellbore tubulars, including
casing or similar structures.
BACKGROUND
[0009] When oil and gas wells are no longer commercially viable,
they must be abandoned in accord with government regulations.
Abandonment requires that the wellbore tubulars, including all
strings of tubing, pipe, casing or liners that comprise the
multiple, nested tubulars be severed below the surface or the mud
line to a specified depth, and removed.
[0010] When cutting multiple, nested tubulars of significant
diameters, for example 95/8 inches outside diameter through 42
inches outside diameter, with at least two other nested tubulars of
different sizes dispersed in between (e.g., 135/8'', 24'', and
30'').
[0011] Mechanical expanding and retracting blade cutters must be
brought back to the surface where successively larger cutting
blades are exchanged for smaller cutting blades. Exchanging the
smaller blades for larger blades allows the downhole cutting of
successively larger diameter multiple, nested tubulars.
[0012] To access the downhole mechanical blade cutter, the user
must trip out or pull the entire work string out of the wellbore
and unscrew each work string joint until the mechanical blade
cutter is removed from the bottom of the work string. After
exchanging the mechanical blade cutter for a larger cutting blade,
the work string joints are screwed back together, one after
another, and tripped back into the wellbore. The mechanical blade
cutter trip back into the wellbore to the previous tubular cut
location for additional cutting is compromised because the length
of the work string varies due to temperature changes or
occasionally human error in marking or counting work string joints.
Consequently, it is difficult to precisely align successive cuts
with earlier cuts.
[0013] Additionally, many installed multiple, nested tubular
strings in wells are non-concentric, meaning that the nested
tubulars are positioned off center in relation to the innermost
tubular. As a result of the multiple, nested tubulars being stacked
or clustered to one side, i.e. non-concentric to each other, the
density or amount of material being cut will vary in a radial
direction from the center of the innermost tubular during cutting.
Mechanical cutter blades sometimes experience breakage when cutting
multiple, nested tubulars positioned non-concentrically in relation
to each other. The blade cutter often breaks from the contact with
the leading edge of a partial segment of the casing that remains
after another segment of that casing has been cut away. The
remaining portion of the casing forms a "C" or horseshoe-type shape
when viewed from above. The blade cutter extends to its fullest
open cut position after moving across a less dense material or open
space (because that material has been cut away) and when the blade
cutter impacts the leading edge of the "C" shaped tubular, the
force may break off the blade. The breaking of a cutter blade
requires again tripping out and then back into the well and
starting over at a different location in the wellbore in order to
attempt severing of the multiple, nested tubulars. Non-concentric,
multiple, nested tubulars present serious difficulties for
mechanical blade cutters. Severing non-concentric multiple, nested
tubulars may take a period of days for mechanical blade
cutters.
[0014] Additionally, existing abrasive waterjet cutters also
experience difficulties and failures to make cuts through multiple,
nested tubulars. Primarily, existing solutions relate to abrasive
waterjet cutting utilizing rotational movement in a substantially
horizontal plane to produce a circumferential cut in downhole
tubulars. However, the prior art in abrasive waterjet et cutters
for casing severance often results in spiraling cuts with narrow
kerfs in which the end point of the attempted circumferential cut
fails to meet the beginning point of the cut after the cutting tool
has made a full 360 degree turn. In other words, the cut does not
maintain an accurate horizontal plane throughout the 360 degree
turn, and complete severance fails to be achieved. Another problem
encountered by existing abrasive waterjet et cutting is the
inability to cut all the way through the thicker, more widely
spaced mass of non-concentrically positioned tubulars. In this
situation, the cut fails to penetrate all the way through on a 360
degree circumferential turn.
[0015] A further disadvantage of traditional abrasive waterjet
cutting is that in order to successfully cut multiple, nested
tubulars downhole, air must be pumped into the well bore to create
an "air pocket" around the area where the cutting is to take place,
such that the abrasive waterjet et tool is not impeded by water or
wellbore fluid. The presence of fluid in the cutting environment
greatly limits the effectiveness of existing abrasive waterjet
cutting.
[0016] Additionally, existing cutting systems fail to provide the
operator with direct confirmation of a complete cut being made.
Instead, existing provide indirect verification such as
verification of severance by welding "ears" on the outside of the
top portion of the tubulars under the platform, attaching hydraulic
lift cylinders, heavy lift beams, and then lifting the entire
conductor (all tubulars) to verify complete detachment has been
achieved. Basically, if the tubulars are able to be lifted from the
well bore, it is assumed the severance was successful. When working
offshore, this lifting verification process occurs before even more
costly heavy lift boats are deployed to the site. This method of
verification is both time-consuming and expensive.
[0017] There exist methods to mill windows via longitudinal,
vertical travel in casing. However, these milling methods do not
completely sever multiple, nested non-concentric tubulars for well
abandonment. One such rotary milling method uses a whipstock, which
must be deployed before the window milling process can begin. A
rotary mill is then actuated against one side of a tubular along
with a means of vertical travel, enabling a window to be cut
through the tubular. However, this method does not permit 360
degree circumferential severance of multiple, nested tubulars and
is not suited for the purpose of well abandonment.
[0018] Conventionally available severing technology requires
multiple trips of the cutting equipment when cutting multiple
nested tubulars, and/or uses explosive shape charges to sever
multiple, nested tubulars in order to remove. These conventionally
available systems either take excessive times in cutting, and/or
have negative environmental impacts.
[0019] A need exists for effective alternatives to conventionally
available cutting systems for multiple nested tubular severance in
well abandonment.
[0020] One embodiment provides a safe and environmentally benign
means of completely severing multiple, nested tubulars for well
abandonment including overcoming the difficulties encountered by
mechanical blade cutting, abrasive waterjet et cutting or other
means of tubular milling currently available.
[0021] While certain novel features of this invention shown and
described below are pointed out in the annexed claims, the
invention is not intended to be limited to the details specified,
since a person of ordinary skill in the relevant art will
understand that various omissions, modifications, substitutions and
changes in the forms and details of the device illustrated and in
its operation may be made without departing in any way from the
spirit of the present invention. No feature of the invention is
critical or essential unless it is expressly stated as being
"critical" or "essential."
[0022] When oil and gas wells are no longer commercially viable,
they must be abandoned in accord with government regulations.
Abandonment requires that the installed tubulars, including all
strings of tubing, pipe, casing or liners that comprise the
multiple, nested tubulars that have been installed in the wellbore,
must be severed below the surface of the earth, or severed below
the ocean floor, and removed. Using explosive shape charges to
sever multiple, nested tubulars in order to remove them has
negative environmental impacts, and regulators worldwide are
limiting the use of explosives. Therefore, a need exists for
effective alternatives to the use of explosives for tubular
severance in well abandonment.
[0023] Mechanical blade cutting and abrasive waterjet et cutting
have been implemented in response to new restrictive environmental
regulations limiting the use of explosives.
[0024] Existing mechanical blade cutters utilized from the inside
of the innermost casing, cutting out through each successive
tubular of the multiple nested tubulars, requires multiple trips in
and out of the wellbore. Such mechanical blade cutters require a
rotary rig or some means of rotary drive in order to rotate the
work string to which the mechanical blade cutter is attached.
Rotary drive systems are both cumbersome and expensive to have at
the work site. Existing mechanical blade cutters are deficient
because, among other reasons, the mechanical blade cutters may
break when they encounter non-concentric tubulars. Another
deficiency is the limitation on the number of nested tubulars that
may be severed by the mechanical blade cutter at one time or trip
into the wellbore. An "inner" and "outer" string may be severable,
if generally concentrically positioned in relation to each other.
However, there is no current capability for severing a multiple
non-concentrically (eccentrically) nested tubulars that provides
consistent time and cost results in a single trip into the
wellbore.
[0025] Most advances in the mechanical blade cutting art have
focused on cut chip control and efficiency, rather than focusing on
the fundamental issues of blade breakage and required, multiple,
undesired trips of the apparatus in and out of a well. Thus these
fundamental problems of existing mechanical blade cutting
persist.
[0026] When cutting multiple, nested tubulars of significant
diameters, for example 95/8 inches outside diameter through 36
inches outside diameter, with at least two other nested tubulars of
different sizes dispersed in between, the mechanical blade cutter
must be brought back to the surface where successive larger cutting
blades are exchanged for smaller cutting blades. Exchanging the
smaller blades for larger blades allows the downhole cutting of
successively larger diameter multiple, nested tubulars.
[0027] To access the downhole mechanical blade cutter, the user
must pull the entire work string out of the wellbore and unscrew
each work string joint until the mechanical blade cutter is removed
from the bottom of the work string. After exchanging the mechanical
blade cutter for a larger cutting blade, the work string joints are
screwed back together, one after another, and tripped back into the
wellbore. The mechanical blade cutter trip back into the wellbore
to the previous tubular cut location for additional cutting is
compromised because the length of the work string varies due to
temperature changes or occasionally human error in marking or
counting work string joints. Consequently, it is difficult to
precisely align successive cuts with earlier cuts.
[0028] Many installed multiple, nested tubular strings in wells are
non-concentric, meaning that the nested tubulars are positioned off
center in relation to the innermost tubular. This is often the case
because the outer tubulars do not have the same center diameter as
the inner tubular. As a result of the multiple, nested tubulars
being stacked or clustered to one side, i.e. non-concentric to each
other, the density or amount of material being cut will vary
circumferentially during cutting. Mechanical cutter blades
sometimes experience breakage when cutting multiple, nested
tubulars positioned non-concentrically in relation to each other.
The blade cutter often breaks from the contact with the leading
edge of a partial segment of the casing that remains after another
segment of that casing has been cut away. The remaining portion of
the casing forms a "C" or horseshoe-type shape when viewed from
above. The blade cutter extends to its fullest open cut position
after moving across a less dense material or open space (because
that material has been cut away) and when the blade cutter impacts
the leading edge of the "C" shaped tubular, the force may break off
the blade. The breaking of a cutter blade requires again tripping
out and then back into the well and starting over at a different
location in the wellbore in order to attempt severing of the
multiple, nested tubulars. Non-concentric, multiple, nested
tubulars present serious difficulties for mechanical blade cutters.
Severing non-concentric multiple, nested tubulars may take a period
of days for mechanical blade cutters.
[0029] Existing abrasive waterjet cutters also experience
difficulties and failures to make cuts through multiple, nested
tubulars. Primarily, existing solutions relate to abrasive waterjet
cutting utilizing rotational movement in a substantially horizontal
plane to produce a circumferential cut in downhole tubulars.
However, the prior art in abrasive waterjet cutters for casing
severance often results in spiraling cuts with narrow kerfs in
which the end point of the attempted circumferential cut fails to
meet the beginning point of the cut after the cutting tool has made
a full 360-degree turn. In other words, the cut does not maintain
an accurate horizontal plane throughout the 360-degree turn, and
complete severance fails to be achieved. Another problem
encountered by existing abrasive waterjet cutting is the inability
to cut all the way through the thicker, more widely spaced mass of
non-concentrically positioned tubulars. In this situation, the cut
fails to penetrate all the way through on a 360-degree
circumferential turn. A further disadvantage of traditional
abrasive waterjet et cutting is that in order to successfully cut
multiple, nested tubulars downhole, air must be pumped into the
well bore to create an "air pocket" around the area where the
cutting is to take place, such that the abrasive waterjet et tool
is not impeded by water or wellbore fluid. The presence of fluid in
the cutting environment greatly limits the effectiveness of
existing abrasive waterjet cutting.
[0030] Existing systems provide, verification of severance by
welding "ears" on the outside of the top portion of the tubulars
under the platform, attaching hydraulic lift cylinders, heavy lift
beams, and then lifting the entire conductor (all tubulars) to
verify complete detachment has been achieved. Basically, if the
tubulars can be lifted from the well bore; it is assumed the
severance was successful. When working offshore, this lifting
verification process occurs before even more costly heavy lift
boats are deployed to the site. This method of verification is both
time-consuming and expensive.
[0031] There exist methods to mill windows via longitudinal,
vertical travel in casing. However, these milling methods do not
completely sever multiple, nested non-concentric tubulars for well
abandonment. One such rotary milling method uses a whipstock, which
must be deployed before the window milling process can begin. A
rotary mill is then actuated against one side of a tubular along
with a means of vertical travel, enabling a window to be cut
through the tubular. However, this method does not permit 360
degree circumferential severance of multiple, nested tubulars and
is not suited for the purpose of well abandonment.
[0032] This invention provides a safe and environmentally benign
means of completely severing multiple, nested tubulars for well
abandonment including overcoming the difficulties encountered by
mechanical blade cutting, abrasive waterjet et cutting or other
means of tubular milling currently available.
BRIEF SUMMARY
[0033] The apparatus of the present invention solves the problems
confronted in the art in a simple and straightforward manner. These
and other objects are attained in accordance with the concepts of
the present invention through the provision of a controllable
downhole cutter.
[0034] In one embodiment a predefined cutting pathway for the
cutting member in the multiple nested tubulars is programmed in the
controller.
[0035] In one embodiment a separate predefined cutting pathway is
defined for each of the tubulars in the multiple nested
tubulars.
[0036] In one embodiment the predefined cutting pathway includes
relative movement of the cutting member in the W, Y, and Z
axes.
[0037] In one embodiment the predefined cutting pathway includes
relative and sequential movement of the cutting member in the W, Y,
and Z axes.
First Cut Tubular
[0038] In one embodiment, cutting member is moved in the Y axis
from the home position to a first cutting position of the first
nested tubular, the first cutting position being closer to the
W-axis than the home cutting position.
[0039] In one embodiment, while in the first cutting position, the
cutting member is rotated at least 360 degrees in the W-axis while
remaining in the first cutting position. In various embodiments at
least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 22,
24, 26, 28, and 30 revolutions are made in the W-axis while cutting
member is maintained in the first cutting position of the Y-axis.
In various embodiments any amount of W-axis revolutions between any
two of the above specified number of revolutions in this paragraph
are made while the cutting member is in the first cutting position
for cutting the first tubular.
[0040] In one embodiment during W-axis rotations, the cutting
member is also moved in the Z-axis. In one embodiment movement is
upwardly in the Z-axis between first and second Z-axis positions
for cutting the first tubular. In one embodiment this upward
movement in the Z-axis causes the cutting member to move in a
spiral pathway (or helical pathway) as the cutting member also
moves in the W-axis simultaneously with the Z-axis. In one
embodiment the vertical movement in the Z-axis is such that the
vertical movement for any one revolution is greater than zero but
less than the vertical height of material cut from the first
tubular being cut by cutting member. In this way, although a spiral
or helical pathway is being made by cutting member a complete cut
about the first tubular is also made.
[0041] In one embodiment the cutting member is moved in the
vertical Z-axis between a first height and a second height for the
first tubular.
[0042] In one embodiment multiple W-axis revolutions of the cutting
member are made causing the height of the overall cut in the first
tubular to be greater than the height made by the cutting member
during one complete W-axis revolution.
[0043] In one embodiment the height of the cut in the first tubular
is equal to the height of a cut made by the cutting member made in
the first tubular with a single W-axis rotation (e.g., when there
is not Z-axis movement of cutting member during W-axis rotation),
plus the difference in heights between the Z-axis position at the
start of the cut of the first tubular to the Z-axis position at the
finish of the cut of the first tubular.
Second Cut Tubular
[0044] In one embodiment, cutting member is moved in the Y axis to
a second cutting position for the second tubular, the second
tubular having a larger diameter than the first tubular, the second
cutting position being closer to the W-axis than the first cutting
position.
[0045] In one embodiment, before the second tubular is cut, the
cutting member is moved from the second height for the first
tubular to the first height for the second tubular, the first
height for the second tubular being between lower than the second
height for the first tubular. In one embodiment the first height
for the second tubular is also lower than the first height for the
first tubular (this can occur where the Y-axis position of the
cutting member for cutting the second tubular is closer to the
W-axis than the Y-axis position for the first tubular, such as when
the second tubular has a larger diameter than the first
tubular).
[0046] In one embodiment, while in the second cutting position, the
cutting member is rotated at least 360 degrees in the W-axis while
remaining in the second cutting position. In various embodiments at
least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 22,
24, 26, 28, and 30 revolutions are made in the W-axis while cutting
member is maintained in the second cutting position of the Y-axis.
In various embodiments any amount of W-axis revolutions between any
two of the above specified number of revolutions in this paragraph
are made while the cutting member is in the second cutting position
for cutting the second tubular.
[0047] In one embodiment during W-axis rotations, the cutting
member is also moved in the Z-axis. In one embodiment movement is
upwardly in the Z-axis between first and second Z-axis positions
for cutting the second tubular. In one embodiment this upward
movement in the Z-axis causes the cutting member to move in a
spiral pathway (or helical pathway) as the cutting member also
moves in the W-axis simultaneously with the Z-axis. In one
embodiment the vertical movement in the Z-axis is such that the
vertical movement for any one revolution is greater than zero but
less than the vertical height of material cut from the second
tubular being cut by cutting member. In this way, although a spiral
or helical pathway is being made by cutting member a complete cut
about the second tubular is also made.
[0048] In one embodiment multiple W-axis revolutions of the cutting
member are made causing the height of the overall cut in the second
tubular to be greater than the height made by the cutting member
during one complete W-axis revolution.
[0049] In one embodiment the height of the cut in the second
tubular is equal to the height of a cut made in the second tubular
by the cutting member made with a single W-axis rotation (e.g.,
when there is not Z-axis movement of cutting member during W-axis
rotation), plus the difference in heights between the Z-axis
position at the start of the cut of the second tubular to the
Z-axis position at the finish of the cut of the second tubular.
[0050] In one embodiment the height of the cut in the second
tubular is less than the height of the cut in the first
tubular.
Third Cut Tubular
[0051] In one embodiment, cutting member is moved in the Y axis to
a third cutting position for the third tubular, the third tubular
having a larger diameter than the second and first tubulars, the
third cutting position being closer to the W-axis than the second
cutting position.
[0052] In one embodiment, before the third tubular is cut, the
cutting member is moved from the second height for the second
tubular to the first height for the third tubular, the first height
for the third tubular being lower than the second height for the
second tubular. In one embodiment the first height for the third
tubular is also lower than the first height for the second tubular
(this can occur where the Y-axis position of the cutting member for
cutting the third tubular is closer to the W-axis than the Y-axis
position for the second tubular, such as when the third tubular has
a larger diameter than the second tubular).
[0053] In one embodiment, while in the third cutting position, the
cutting member is rotated at least 360 degrees in the W-axis while
remaining in the third cutting position. In various embodiments at
least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 22,
24, 26, 28, and 30 revolutions are made in the W-axis while cutting
member is maintained in the third cutting position of the Y-axis.
In various embodiments any amount of W-axis revolutions between any
two of the above specified number of revolutions in this paragraph
are made while the cutting member is in the third cutting position
for cutting the third tubular.
[0054] In one embodiment during W-axis rotations, the cutting
member is also moved in the Z-axis. In one embodiment movement is
upwardly in the Z-axis between first and second Z-axis positions
for cutting the third tubular. In one embodiment this upward
movement in the Z-axis causes the cutting member to move in a
spiral pathway (or helical pathway) as the cutting member also
moves in the W-axis simultaneously with the Z-axis. In one
embodiment the vertical movement in the Z-axis is such that the
vertical movement for any one revolution is greater than zero but
less than the vertical height of material cut from the third
tubular being cut by cutting member. In this way, although a spiral
or helical pathway is being made by cutting member a complete cut
about the third tubular is also made.
[0055] In one embodiment multiple W-axis revolutions of the cutting
member are made causing the height of the overall cut in the third
tubular to be greater than the height made by the cutting member
during one complete W-axis revolution.
[0056] In one embodiment the height of the cut in the third tubular
is equal to the height of a cut made in the third tubular by the
cutting member made with a single W-axis rotation (e.g., when there
is not Z-axis movement of cutting member during W-axis rotation),
plus the difference in heights between the Z-axis position at the
start of the cut of the third tubular to the Z-axis position at the
finish of the cut of the third tubular.
[0057] In one embodiment the height of the cut in the third tubular
is less than the height of the cut in the second tubular which is
less than the height of the cut in the first tubular.
Fourth Cut Tubular
[0058] In one embodiment, cutting member is moved in the Y axis to
a fourth cutting position for the fourth tubular, the fourth
tubular having a larger diameter than the third, second, and first
tubulars, the fourth cutting position being closer to the W-axis
than the third cutting position.
[0059] In one embodiment, before the fourth tubular is cut, the
cutting member is moved from the second height for the third
tubular to the first height for the fourth tubular, the first
height for the fourth tubular being lower than the second height
for the third tubular. In one embodiment the first height for the
fourth tubular is also lower than the first height for the third
tubular (this can occur where the Y-axis position of the cutting
member for cutting the fourth tubular is closer to the W-axis than
the Y-axis position for the third tubular, such as when the fourth
tubular has a larger diameter than the third tubular).
[0060] In one embodiment, while in the fourth cutting position, the
cutting member is rotated at least 360 degrees in the W-axis while
remaining in the fourth cutting position. In various embodiments at
least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 22,
24, 26, 28, and 30 revolutions are made in the W-axis while cutting
member is maintained in the fourth cutting position of the Y-axis.
In various embodiments any amount of W-axis revolutions between any
two of the above specified number of revolutions in this paragraph
are made while the cutting member is in the fourth cutting position
for cutting the fourth tubular.
[0061] In one embodiment during W-axis rotations, the cutting
member is also moved in the Z-axis. In one embodiment movement is
upwardly in the Z-axis between first and second Z-axis positions
for cutting the fourth tubular. In one embodiment this upward
movement in the Z-axis causes the cutting member to move in a
spiral pathway (or helical pathway) as the cutting member also
moves in the W-axis simultaneously with the Z-axis. In one
embodiment the vertical movement in the Z-axis is such that the
vertical movement for any one revolution is greater than zero but
less than the vertical height of material cut from the fourth
tubular being cut by cutting member. In this way, although a spiral
or helical pathway is being made by cutting member a complete cut
about the fourth tubular is also made.
[0062] In one embodiment multiple W-axis revolutions of the cutting
member are made causing the height of the overall cut in the fourth
tubular to be greater than the height made by the cutting member
during one complete W-axis revolution.
[0063] In one embodiment the height of the cut in the fourth
tubular is equal to the height of a cut made in the fourth tubular
by the cutting member made with a single W-axis rotation (e.g.,
when there is not Z-axis movement of cutting member during W-axis
rotation), plus the difference in heights between the Z-axis
position at the start of the cut of the fourth tubular to the
Z-axis position at the finish of the cut of the fourth tubular.
[0064] In one embodiment the height of the cut in the fourth
tubular is less than the height of the cut in the third tubular,
which is less than the height of the cut in the second tubular,
which is less than the height of the cut in the first tubular.
N.sup.th Cut Tubular
[0065] The method for higher numbers of tubulars than 4 is similar
with similar changes to the procedure as shown between the
methodologies for cuts of the 3.sup.rd and 4.sup.th tubulars.
Multiple Tubulars Cut Simultaneously or Sequentially
[0066] In various embodiments, for a particular Y axis position,
elongated cutting member can cut multiple tubulars simultaneously,
instead of sequentially.
[0067] In one embodiment a first nested tubular is cut
individually, and the next two nested tubulars are cut
simultaneously.
[0068] In one embodiment the first two nested tubulars are cut
simultaneously, and the next larger tubular is cut by
sequentially.
[0069] In one embodiment a first two nested tubulars are cut
simultaneously, and the next two nested tubulars are cut
sequentially.
[0070] In one embodiment a first two nested tubulars are cut
simultaneously, and in a separate step the next two nested tubulars
are cut simultaneously.
Information Provided on Cutting Variables
[0071] One embodiment includes a remote display which includes a
rendering of the nested tubulars, the cutting head, along with a
substantially real time display of the cut made in the tubulars by
the cutting head.
[0072] Display represents cut made through one tubular, a second
tubular, a third tubular, a fourth tubular, etc.
[0073] Display represents cut not yet made through one tubular, a
second tubular, a third tubular, a fourth tubular, etc.
[0074] In one embodiment the cut made in one or more of the
tubulars is shown on the remote display as a graphically removed
portion of the tubular cut, and the remaining portion of the
tubular is shown as not being cut.
[0075] In one embodiment the tubulars and/or cut made are shown in
perspective or three dimensional views.
[0076] In one embodiment a depiction of the cutting member is shown
on the remote display. In one embodiment the depiction of the
cutting member on the display corresponds to the orientation (e.g.,
W and Y axis orientations) of the elongated cutting member actually
making the cut.
[0077] In one embodiment a depiction of the cutting member is shown
on the remote display. In one embodiment the depiction of the
cutting member on the display corresponds to the vertical position
(e.g., Z axis position) of the elongated cutting member actually
making the cut.
[0078] In one embodiment the orientation and/or position of the
depiction of the cutting member on the display is shown relative to
pre-selected home positions for starting W, Z, and/or Y axes
position(s).
[0079] In one embodiment sensors are operably attached to the
apparatus, and one or more of these sensors send the controller
positional information relative to the cutting member's W, Z,
and/or Y axes positions, and at least some of this information is
used to display information on the remote display regarding the
cutting member's W, Z, and/or Y axial positions.
[0080] In one embodiment information relative to the cutting
members W, Z, and/or Y axes positions is displayed on the remote
display. In one embodiment it is graphically displayed through
pictorial representations of the cutting member. In one embodiment
information relative to the cutting members W, Z, and/or Y axes
positions is graphically displayed on the remote display. In one
embodiment information relative to the cutting members W, Z, and/or
Y axes positions is numerically displayed on the remote
display.
[0081] In one embodiment sensors are operably attached to the
apparatus, and one or more of these sensors send the controller
speed information regarding the cutting member's rotational speed
in the W axis, and at least some of this information is used to
display information on the remote display regarding the cutting
member's rotational speed in the W axis.
[0082] In one embodiment sensors are operably attached to the
apparatus, and one or more of these sensors send the controller
speed information regarding the cutting member's angular/rotational
speed in the Y axis, and at least some of this information is used
to display information on the remote display regarding the cutting
member's angular/rotational speed in the Y axis.
[0083] In one embodiment sensors are operably attached to the
apparatus, and one or more of these sensors send the controller
speed information regarding the cutting member's linear speed in
the Z axis, and at least some of this information is used to
display information on the remote display regarding the cutting
member's linear speed in the Z axis.
[0084] In one embodiment sensors are operably attached to the
apparatus, and one or more of these sensors send the controller
speed information regarding the cutting member's rotational speed
of the cutting member about the cutting member's rotational axis,
and at least some of this information is used to display
information on the remote display regarding the cutting member's
rotational speed about the cutting member's rotational axis.
Remote Display
[0085] In one embodiment a remote display is provided providing
substantially real time information to an operator. In one
embodiment the display is remote from the tool and located on a
vessel close to a control panel for the tool. In one embodiment the
display can be the screen of a computer. In one embodiment the
display can be the screen of a portable computing device such as
laptop, notebook, I-Pad, etc.
[0086] In one embodiment a numeral value is provided for the value
being displayed. In one embodiment an X-Y Cartesian graphical
component is provided for the value being displayed. In one
embodiment a pictorial representation is provided for the value
being displayed. In various embodiments combinations of two or more
of these display options are provided for the value being
displayed. In one embodiment a user is provide the option to select
between one or more of these display options for one or more of the
values being displayed.
Rotation of Elongated Cutting Member about its
Longitudinal Axis of Rotation ("ECMLAR") Display
[0087] In one embodiment an indicator is displayed relating to
rotation of the elongated cutting member about its longitudinal
axis of rotation ("ECMLACM"). In one embodiment the display is on
the remote display. In one embodiment the display corresponds to
the total amount of translated angular rotation of the elongated
cutting member in the ECMLAR from a pre-selected home position for
movement in the ECMLAR. In one embodiment the display corresponds
to the relative amount of angular rotation of the elongated cutting
member in the ECMLAR from a pre-selected home position for movement
in the ECMLAR. In one embodiment the display corresponds to the
amount of translated angular rotation of the elongated cutting
member in the ECMLAR. In one the display corresponds to the speed
of angular rotation of the elongated cutting member in the ECMLAR
(e.g., degrees per second, radians per second, and/or revolutions
per minute). In one the display corresponds to the amount of force
applied by the elongated cutting member in the ECMLAR. In one the
display corresponds to the amount of reaction force applied to the
elongated cutting member in the ECMLAR.
W-Axis
[0088] In one embodiment an indicator is displayed relating to
W-axis rotation of the cutting head. In one embodiment the amount
of W-axis rotation of the cutting head is about equal to the amount
of W-axis rotation of the cutting member. In one embodiment the
display is on the remote display. In one embodiment the display
corresponds to the amount of translated angular rotation of the
cutting head in the W-axis from a pre-selected home position for
movement in the W-axis. In one embodiment the display corresponds
to the relative amount of angular rotation of the cutting head in
the W-axis from a pre-selected home position for movement in the
W-axis. In one embodiment the display corresponds to the amount of
translated angular rotation of the cutting head in the W-axis. In
one the display corresponds to the speed of angular rotation of the
cutting head in the W-axis (e.g., degrees per second, radians per
second, and/or revolutions per minute). In one the display
corresponds to the amount of force applied by the cutting head in
the W-axis. In one the display corresponds to the amount of
reaction force applied to the cutting head in the W-axis.
Y-Axis Display
[0089] In one embodiment an indicator is displayed relating to
Y-axis pivoting of the cutting member relative to the cutting head.
In one embodiment the display is on the remote display. In one
embodiment the display corresponds to the total amount of
translated angular pivoting rotation of the cutting member in the
Y-axis from a pre-selected home position for pivoting in the
Y-axis. In one embodiment the display corresponds to the relative
amount of angular pivoting of the cutting member in the Y-axis from
a pre-selected home position for movement in the Y-axis. In one
embodiment the display corresponds to the total amount of
translated angular pivoting of the cutting member in the Y-axis. In
one the display corresponds to the speed of angular pivoting of the
cutting member in the Y-axis (e.g., degrees per second, radians per
second, and/or revolutions per minute). In one the display
corresponds to the amount of force applied by the cutting member in
the Y-axis. In one the display corresponds to the amount of
reaction force applied to the cutting member in the Y-axis.
Z-Axis Display
[0090] In one embodiment an indicator is displayed relating to
Z-axis linear movement of the cutting head relative to the body of
the system. In one embodiment the amount of Z-axis linear movement
of the cutting head is about equal to the amount of Z-axis linear
movement of the cutting member. In one embodiment the display is on
the remote display. In one embodiment the display corresponds to
the amount of translated linear movement of the cutting head in the
Z-axis from a pre-selected home position for movement in the
Z-axis. In one embodiment the display corresponds to the relative
amount of linear movement of the cutting head in the Z-axis from a
pre-selected home position for movement in the Z-axis. In one
embodiment the display corresponds to the amount of translated
linear movement of the cutting head in the Z-axis. In one the
display corresponds to the speed of linear movement of the cutting
head in the Z-axis (e.g., length per unit time such as cm/sec). In
one the display corresponds to the amount of force applied by the
cutting head in the Z-axis. In one the display corresponds to the
amount of reaction force applied to the cutting head in the
Z-axis.
[0091] In one embodiment time for a cut of a first tubular in a
plurality of nested tubulars is displayed on a display. In one
embodiment time for a cut of a second tubular in a plurality of
nested tubulars is displayed on a display. In one embodiment time
for a cut of a third tubular in a plurality of nested tubulars is
displayed on a display. In one embodiment time for a cut of a
fourth tubular in a plurality of nested tubulars is displayed on a
display. In one embodiment time for a cut of an n.sup.th tubular in
a plurality of "n" nested tubulars is displayed on a display.
[0092] In one embodiment total time from start of cut of the first
tubular to the time elapsed from the cut on the current cut of the
n.sup.th tubular in a plurality of "n" nested tubulars is
displayed.
Warnings or Alarms
[0093] In one embodiment the method and apparatus can provide one
or more alarms depending on the conditions being monitored on the
method and apparatus. In various embodiments the one or more alarms
can be audible and/or visual.
[0094] In various embodiments described in this section an alarm
can be provided if a particular quantity being monitored exceeds or
falls below a predefined value, or fails to meet or exceed a
predefined value within a predefined period of time.
[0095] In various embodiments the predefined period of time can be
0.1, 0.5, 1, 2, 3, 4, 5, 10, 15, 20, 30, and/or 60 seconds. In
various embodiments the predefined period of time can be the range
between any two of these predefined periods of time.
[0096] In various embodiments an alarm is provided where a quantity
being monitored exceeds or falls below the following percentage of
the predefined value by 0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 15, 20, 25, 30, 35, 40, 45, and/or 50 percent. In various
embodiments the predefined period of time can be the range between
any two of these predefined periods of time.
Alarm for Rotation of Elongated Cutting Member about its
Longitudinal Axis of Rotation ("ECMLAR")
[0097] In one embodiment, for a particular nested tubular to be
cut, an alarm can be provided where the total amount of translated
angular rotation of the elongated cutting member in the ECMLAR from
a pre-selected home position for movement in the ECMLAR when
cutting a particular tubular fails to reach a preselected target
amount within a predefined period of time. In one an alarm can be
provided where the relative amount of translated angular rotation
of the elongated cutting member in the ECMLAR from a pre-selected
home position for movement in the ECMLAR when cutting a particular
tubular fails to reach a preselected target amount within a
predefined period of time. In one embodiment an alarm is provided
when the speed of angular rotation of the elongated cutting member
in the ECMLAR (e.g., degrees per second, radians per second, and/or
revolutions per minute) falls below or exceeds a predefined
percentage (or range) of a preselected target value of angular
rotation. In one embodiment an alarm is provided when the amount of
applied force by the elongated cutting member in the ECMLAR falls
below or exceeds a predefined percentage (or range) of a
preselected target value of force. In one embodiment an alarm is
provided when the amount of reaction force applied on the elongated
cutting member in the ECMLAR falls below or exceeds a predefined
percentage (or range) of a preselected target value of force.
[0098] In various embodiments pressure of hydraulic fluid powering
to the elongated cutting member is considered standard at a
pressure of 2,000 psi. In various embodiments the supply pressure
is standard at 1,500, 1,600, 1,700, 1,800, 1,900, 2,000, 2,100,
2,200, 2,300, 2,400, 2,500, 2,600, 2,700, 2,800, 2,900, 3,000,
3,500, 4,000, 4,500, and/or 5,000 psi. In various embodiments the
standard pressure can be within a range between any two of the
specified pressures.
[0099] In various embodiments an alarm is provided where the
pressure of fluid powering the elongated cutting member exceeds or
falls below the following percentage of the standard pressures by
0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25,
30, 35, 40, 45, and/or 50 percent. In various embodiments the
warning range be between any two of these percentages.
[0100] In various embodiments the torque applied by the elongated
cutting member by rotation about its longitudinal axis is
considered standard at 350 ft-lbs. In various embodiments the
applied torque by rotation is standard at 100, 150, 200, 250, 300,
350, 400, 450, 500, 700, 750, 800, 900, 1,000, 1,100, 1,200, 1,300,
1,400, 1,500, 1,600, 1,700, 1,800, 1,900, 2,000, 2,500, and/or
3,000 ft-lbs. In various embodiments the standard torque by
rotation can be within a range between any two of the specified
torques.
[0101] In various embodiments an alarm is provided where the torque
applied by rotation of the elongated cutting member exceeds or
falls below the following percentage of the standard torques by
0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25,
30, 35, 40, 45, and/or 50 percent. In various embodiments the
warning range be between any two of these percentages.
[0102] In various embodiments the rotational speed of the elongated
cutting member about its longitudinal axis is considered standard
at 350 rpms. In various embodiments the standard rotational speed
is 100, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 900,
1,000, and/or 1,500 rpms. In various embodiments the standard
rotational speed can be within a range between any two of the
specified rotational speeds.
[0103] In various embodiments an alarm is provided where the
rotational speed of the elongated cutting member exceeds or falls
below the following percentage of the standard rotational speed by
0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25,
30, 35, 40, 45, and/or 50 percent. In various embodiments the
warning range be between any two of these percentages.
W-Axis Alarm
[0104] In one embodiment, for a particular nested tubular to be
cut, an alarm can be provided where the total amount of translated
rotation of the cutting head in the W-axis from a pre-selected home
position for movement in the W-axis fails to reach a preselected
target amount within a predefined period of time. In one an alarm
can be provided where the relative amount of rotation of the
cutting head in the W-axis from a pre-selected home position for
movement in the W-axis, during a particular cut of a particular
nested tubular, fails to reach a preselected target amount within a
predefined period of time. In one embodiment an alarm is provided
when the speed of angular rotation of the cutting head in the
W-axis (e.g., degrees per second, radians per second, and/or
revolutions per minute) falls below or exceeds a predefined
percentage (or range) of a preselected target value of angular
rotation. In one embodiment an alarm is provided when the amount of
applied force by cutting head in the W-axis falls below or exceeds
a predefined percentage (or range) of a preselected target value of
force. In one embodiment an alarm is provided when the amount of
reaction force applied on the cutting head in the W-axis falls
below or exceeds a predefined percentage (or range) of a
preselected target value of force.
[0105] In various embodiments pressure of hydraulic fluid powering
rotation of the cutting head about the W-axis is considered
standard at a pressure of 1,000 psi. In various embodiments the
supply pressure is standard at 500, 600, 700, 800, 900, 1,000,
1,100, 1,200, 1,300, 1,400, 1,500, 1,600, 1,700, 1,800, 1,900,
2,000, and/or 2,500 psi. In various embodiments the standard
pressure can be within a range between any two of the specified
pressures.
[0106] In various embodiments an alarm is provided where the
pressure of fluid powering rotation of the cutting head about the
W-axis exceeds or falls below the following percentage of the
standard pressures by 0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8,
9, 10, 15, 20, 25, 30, 35, 40, 45, and/or 50 percent. In various
embodiments the warning range be between any two of these
percentages.
[0107] In various embodiments the torque applied by rotation of the
cutting head in the W-axis is considered standard at 750 ft-lbs. In
various embodiments the applied torque by rotation is standard at
50, 100, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 750,
800, 900, 1,000, 1,500, and/or 2,000 ft-lbs. In various embodiments
the standard torque by rotation of cutting head in the W-axis can
be within a range between any two of the specified torques.
[0108] In various embodiments an alarm is provided where the torque
applied by rotation of the cutting head in the W-axis exceeds or
falls below the following percentage of the standard torques by
0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25,
30, 35, 40, 45, and/or 50 percent. In various embodiments the
warning range be between any two of these percentages.
[0109] In various embodiments the rotational speed of the cutting
head in the W-axis is considered standard at 1 rpm. In various
embodiments the standard rotational speed is 0.1, 0.2, 0.3, 0.4,
0.5, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5 and/or 5
rpms. In various embodiments the standard rotational speed can be
within a range between any two of the specified rotational
speeds.
[0110] In various embodiments an alarm is provided where the
rotational speed of the cutting head in the W-axis exceeds or falls
below the following percentage of the standard rotational speed by
0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25,
30, 35, 40, 45, and/or 50 percent. In various embodiments the
warning range be between any two of these percentages.
Y-Axis Alarm
[0111] In one embodiment, for a particular nested tubular to be
cut, an alarm can be provided where the cutting member, from a
pre-selected home position in the Y-axis, fails to reach a
preselected target Y-axis cutting position, within a predefined
period of time. In one embodiment an alarm is provided when the
amount of applied force by the cutting member in the Y-axis falls
below or exceeds a predefined percentage (or range) of a
preselected target value of force. In one embodiment an alarm is
provided when the amount of reaction force applied on the cutting
member in the Y-axis falls below or exceeds a predefined percentage
(or range) of a preselected target value of force.
[0112] In various embodiments pressure of hydraulic fluid powering
pivoting of the elongated cutting member in the Y-axis is
considered standard at a pressure of 1,000 psi. In various
embodiments the supply pressure is standard at 100, 200, 300, 400,
500, 600, 700, 800, 900, 1,000, 1,100, 1,200, 1,300, 1,400, 1,500,
1,600, 1,700, 1,800, 1,900, 2,000, 2,500, 2,600, 2,700, 2,800,
2,900 and/or 3,000 psi. In various embodiments the standard
pressure can be within a range between any two of the specified
pressures.
[0113] In various embodiments an alarm is provided where the
pressure of fluid powering pivoting of the elongated cutting member
in the Y-axis exceeds or falls below the following percentage of
the standard pressures by 0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, and/or 50 percent. In
various embodiments the warning range be between any two of these
percentages.
[0114] In various embodiments the force applied by the elongated
cutting head being pivoted in the Y-axis is considered standard at
2000 lbs. In various embodiments the applied torque by rotation is
standard at 100, 200, 300, 400, 500, 600, 700, 800, 900, 1,000,
1,500, 2,000, 2,500, 3,000, 3,500, 4,000, 4,500 and/or 5,000 lbs.
In various embodiments the standard force applied in the Y-axis can
be within a range between any two of the specified applied
forces.
[0115] In various embodiments an alarm is provided where the force
applied in the Y-axis exceeds or falls below the following
percentage of the standard torques by 0.1, 0.25, 0.5, 0.75, 1, 2,
3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, and/or 50
percent. In various embodiments the warning range be between any
two of these percentages.
[0116] In various embodiments the pivoting speed of the elongated
cutting member in the Y-axis is considered standard at 1 rpm. In
various embodiments the standard pivoting speed is 0.1, 0.2, 0.3,
0.4, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5 and/or 5
rpms. In various embodiments the standard rotational speed can be
within a range between any two of the specified rotational speeds.
It is understood that the elongated cutting member only pivots in
the Y-axis (and does not complete rotate so that rpms can be
converted to radians per second or degrees per second).
[0117] In various embodiments an alarm is provided where the
pivoting speed of the elongated cutting member in the Y-axis
exceeds or falls below the following percentage of the standard
rotational speed by 0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8,
9, 10, 15, 20, 25, 30, 35, 40, 45, and/or 50 percent. In various
embodiments the warning range be between any two of these
percentages.
Z-Axis Alarm
[0118] In one embodiment, for a particular nested tubular to be
cut, an alarm can be provided where the cutting head, from a
pre-selected home position in the Z-axis, fails to reach a
preselected target starting Z-axis cutting position, within a
predefined period of time. In one embodiment the amount of Z-axis
linear movement of the cutting head is about equal to the amount of
Z-axis linear movement of the cutting member. In one embodiment,
for a particular nested tubular to be cut, an alarm can be provided
where the cutting head, from a pre-selected home position in the
Z-axis, fails to reach a preselected target finishing Z-axis
cutting position, within a predefined period of time. In one
embodiment the predefined period of time for achieving the Z-axis
finishing time starts immediately after reaching the preselected
target starting Z-axis cutting position. In one embodiment the
predetermined period of time for achieving the Z-axis target
starting position for the next tubular in a chain of nested
tubulars starts immediately after reaching the preselected target
finishing Z-axis cutting position of the last cut tubular. In one
embodiment an alarm is provided when the linear speed of motion of
the cutting head in the Z-axis falls below or exceeds a predefined
percentage (or range) of a preselected target value of linear
speed. In one embodiment an alarm is provided when the amount of
applied force by the cutting head in the Z-axis falls below or
exceeds a predefined percentage (or range) of a preselected target
value of force. In one embodiment an alarm is provided when the
amount of reaction force applied on the cutting head in the Z-axis
falls below or exceeds a predefined percentage (or range) of a
preselected target value of force.
[0119] In various embodiments pressure of hydraulic fluid powering
movement of the cutting head in the Z-axis is considered standard
at a pressure of 1,100 psi. In various embodiments the supply
pressure is standard at 500, 600, 700, 800, 900, 1,000, 1,100,
1,200, 1,300, 1,400, 1,500, 1,600, 1,700, 1,800, 1,900, 2,000,
and/or 2,500 psi. In various embodiments the standard pressure can
be within a range between any two of the specified pressures.
[0120] In various embodiments an alarm is provided where the
pressure of fluid powering movement of the cutting head in the
Z-axis exceeds or falls below the following percentage of the
standard pressures by 0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8,
9, 10, 15, 20, 25, 30, 35, 40, 45, and/or 50 percent. In various
embodiments the warning range be between any two of these
percentages.
[0121] In various embodiments the force applied by movement of the
cutting head in the Z-axis is considered standard at 500 lbs (above
the weight of the cutting head). In various embodiments the applied
torque by rotation is standard at 50, 100, 150, 200, 250, 300, 350,
400, 450, 500, 600, 700, 800, 900, 1,000, 1,500, 2,000, 2,500
and/or 3,000 lbs. In various embodiments the standard linear force
by movement of cutting head in the Z-axis can be within a range
between any two of the specified forces.
[0122] In various embodiments an alarm is provided where the linear
force applied by movement of the cutting head in the Z-axis exceeds
or falls below the following percentage of the standard torques by
0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25,
30, 35, 40, 45, and/or 50 percent. In various embodiments the
warning range be between any two of these percentages.
[0123] In various embodiments the linear speed of the cutting head
in the Z-axis is considered standard at 1 inch per minute. In
various embodiments the standard linear speed is 0.1, 0.2, 0.3,
0.4, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5 and/or 5
inches per minute. In various embodiments the standard linear speed
can be within a range between any two of the specified linear
speeds.
[0124] In various embodiments an alarm is provided where the linear
speed of the cutting head in the Z-axis exceeds or falls below the
following percentage of the standard linear speed by 0.1, 0.25,
0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40,
45, and/or 50 percent. In various embodiments the warning range be
between any two of these percentages.
Alarm for Loss of Hydraulic Fluid
[0125] Occasionally a tear or other obstruction or flow anomaly may
occur in the fluid delivery lines of a downhole cutter.
Traditionally, the level of a large fluid tank, for example
hydraulic fluid, would be monitored. If the level started
decreasing, then the operators knew there was a problem.
Unfortunately, this routinely occurs only after some significant
amount of fluid is lost downhole (e.g. 20-30 gallons). Furthermore,
the operators only know there is a problem, they have no idea which
hose had the leak.
[0126] In one embodiment, contrary to traditional models, in
addition to the traditional "level" monitoring, hoses to and from
the tool are fitted with turbine flow meters to continuously
monitor the flow of fluid through each hose. Continuous monitoring
of flow into and out of the tool provides a very early warning
system to alert operators to any flow anomalies. For example,
should a hose develop a tear and begin leaking fluid into the
wellbore, the "delivery" hose would have a flow rate in excess of
the "return" hose. If the difference in the flow meters exceeded a
defined threshold, an operator could be alerted. This is an
improvement over traditional fluid "level" monitoring which could
only detect tears after a significant amount of fluid was lost
downhole, wasting money and creating potential environmental
hazards. Further, traditional "level" monitoring could only detect
flow anomalies that resulted in the loss of fluid. By utilizing
turbine flow meters, pinched, partially blocked/clogged, and/or
completely blocked/clogged hoses can be detected. Also, because
each hose has its own turbine flow meter, the operator can
immediately identify which hose is having the flow anomaly and how
serious the flow anomaly is.
[0127] In various embodiments an alarm is provided where the amount
of fluid flow entering the tool exceeds the amount of fluid flow
returning from the tool by a predefined limit (e.g., 1 gallon per
minute). In various embodiments the standard for discrepancies
between inlet and returning flows about 0.1, 0.2, 0.3, 0.4, 0.5,
0.75, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 7, 8, 9,
10, 12, 14, 15, 16, 18, 20, 25, and/or 30 gallons per minute. In
various embodiments the standard for discrepancy in fluid flow can
be a range between any two of the specified flow standards, and an
alarm is sent when the discrepancy falls above the range (or
outside the range).
[0128] In various embodiments the standard for discrepancies
between inlet and returning flows about exceeds (or falls below)
the following percentage of the standard discrepancies by 0.1,
0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35,
40, 45, and/or 50 percent.
Programming Profile for Plurality of N Tubulars to be Cut
[0129] In one embodiment, while onsite for a cut to be made in a
plurality of n nested tubulars, a user can input into the method
and apparatus size and quantity information for one or more of n
tubulars to be cut by the method and apparatus. In one embodiment
the user can input cross sectional size and thickness data for one
or more of n tubulars to be cut by the method and apparatus (for
example 12 inch diameter with a 1 inch wall thickness).
[0130] In one embodiment the user can input cross sectional size
and thickness data for each of n tubulars to be cut by the method
and apparatus (for example 12 inch diameter with a 1 inch wall
thickness).
[0131] In one embodiment the user can input estimated offset
information (relative to the smallest diameter tubular) for each of
n tubulars to be cut by the method and apparatus (e.g., the amount
of offset of tubular 2 compared to the innermost or smallest
diameter tubular, such as a 1/2 inch offset).
[0132] In one embodiment, based on the size and thickness
information for one or more of the plurality of N nested tubulars
the method and apparatus will determine, for the cut of each nested
tubular: (a) a target Y-axis cutting position of the elongated
cutting member relative to a preselected Y-axis home position, and
(b) target starting and finishing Z-axis cutting positions for the
cutting head (e.g., for the tubular being cut to provide a desired
finished gap or swath or cut), relative to a preselected Z-axis
home position. In one embodiment the method and apparatus will also
determine a target amount of total W-axis rotation or the cutting
head relative to a preselected W-axis home position. These
determinations can be made by the method and apparatus based on the
calculated amount of cut which will be made by the elongated
cutting member (based on the elongated cutting member's size and
length), along with the relative sizes and positions of each of the
plurality of n nested tubulars to be cut.
[0133] In one embodiment, based on the size and thickness
information for one or more of the plurality of n nested tubulars,
the method and apparatus will determine, for the cut of each nested
tubular, a target speed (e.g., degrees per second, radians per
second, and/or revolutions per minute) for the elongated cutting
member's rotation about the ECMLAR.
[0134] In one embodiment the absolute value of the differences
between the target starting and finishing Z-axis cutting positions
for the cutting head decrease as the diameter of the tubular being
cut increases.
[0135] In one embodiment the body of the apparatus remains anchored
in a single longitudinal position in the innermost nested tubular.
In this embodiment, for a n.sup.th nested tubular to be cut, the
cutting head if lowered longitudinally the starting Z-axis position
for the particular n.sup.th nested tubular to be cut, and during
the cut the cutting head is moved upwardly to the finishing Z-axis
position for the particular n.sup.th nested tubular being cut. In
this embodiment the Z-axis finishing position for the first or
innermost nested tubular to be cut is higher than the Z-axis
finishing position for the next nested tubular to be cut (e.g.,
tubular 2), which is higher than the Z-axis finishing position for
the next nested tubular to be cut (e.g., tubular 3), which is
higher than the Z-axis finishing position for the next nested
tubular to be cut (e.g., tubular 4), and so on in this manner. Also
in this embodiment the absolute value of the differences between
the target starting and finishing Z-axis cutting positions for the
cutting head decrease with the higher numbered tubulars. This
embodiment will see a series of gaps or cuts in the nested tubulars
which decrease in size with each successive numbered tubular, and
which are spaced between the cut or gap of each of the smaller
number/diameter nested tubulars.
[0136] In one embodiment the Z-axis starting position for the first
or innermost nested tubular to be cut is about equal to the Z-axis
starting position for the next nested tubular to be cut (e.g.,
tubular 2), which is about equal to the Z-axis starting position
for the next nested tubular to be cut (e.g., tubular 3), which is
about equal to the Z-axis starting position for the next nested
tubular to be cut (e.g., tubular 4), and so on in this manner.
[0137] In one embodiment the Z-axis starting position for the first
or innermost nested tubular to be cut is lower than the Z-axis
starting position for the next nested tubular to be cut (e.g.,
tubular 2), which is lower than the Z-axis starting position for
the next nested tubular to be cut (e.g., tubular 3), which is lower
than the Z-axis starting position for the next nested tubular to be
cut (e.g., tubular 4), and so on in this manner.
[0138] In one embodiment the user can input information on the
annular spaces between the plurality of n nested tubulars to be cut
by the method and apparatus (e.g., between tubular 1 and 2 is
cement, between tubular 2 and 3 is open space, etc.).
[0139] In various embodiments, for one or more of the nested
tubulars to be cut, a pictorial display can be provided on a
tubular by tubular basis (e.g., the proposed cut to be made in the
innermost tubular can be pictorially displayed as complete, and
then the cuts to be made in the first two innermost tubulars can be
pictorially displayed as complete, and so on).
[0140] In various embodiments, for one or more of the nested
tubulars to be cut, the user can override one or more target values
for movements in Y-axis (e.g., target cutting position for a
particular tubular), Z-axis (e.g., starting and finishing Z-axis
locations for a particular tubular), W-axis (e.g., angular
rotational speed), and/or ECMLAR (e.g., angular rotational speed).
In various embodiments, based on particular programming overrides
by the user, the user can be provided on the display a pictorial
representation of the cuts which will be made in the plurality of
nested tubulars by the method and apparatus with the programmed
changes. In various embodiments the pictorial display can be done
an a tubular by tubular basis (e.g., the proposed cut to be made in
the innermost tubular can be pictorially displayed as complete, and
then the cuts to be made in the first two innermost tubulars can be
pictorially displayed as complete, and so on. In this way the user
can be provided with a pictorial depiction of the cuts which will
be made based on his programmed override.
Warnings or Alarms
[0141] In one embodiment the method and apparatus can provide one
or more alarms depending on the conditions being monitored on the
method and apparatus. In various embodiments the one or more alarms
can be audible and/or visual.
[0142] In various embodiments the method and apparatus can be used
in different applications, including but not limited to:
[0143] (a) Land based down hole cutting for the removing of a
wellbore.
[0144] (b) Down hole window cutting for access to additional casing
strings for well plug and abandonment.
[0145] (c) Down hole window cutting for well relief
[0146] The drawings constitute a part of this specification and
include exemplary embodiments to the invention, which may be
embodied in various forms.
[0147] This invention provides methodology and apparatus for
efficiently severing installed multiple, nested strings of
tubulars, either concentric or eccentric, as well as cement or
other material in the annuli between the tubulars, in a single trip
into a well bore in an environmentally sensitive manner without the
need for a rig.
[0148] The invention utilizes a computer-controlled robotic
downhole rotary mill to effectively generate a shape(s) or
profile(s) through, or completely sever in a 360 degree horizontal
circumferential plane, the installed tubing, pipe, casing and
liners as well as cement or other material that may be encountered
in the annuli between the tubulars. This process occurs under
programmable robotic, computerized control, making extensive use of
digital and or analogue sensor data to enable algorithmic, robotic
actuation of the downhole assembly and robotic rotary mill
cutter.
[0149] The robotic rotary mill (downhole assembly) is deployed
inside the innermost tubular to a predetermined location and, the
downhole assembly is locked securely into the innermost tubular and
under computer control, a rotary mill cuts outward and radially and
vertically, cutting away tubulars and cement thus creating a void
(or swath) while completely severing the installed tubing, pipe,
casing and liners as well as cement or other material that may be
encountered in the annuli between the tubulars. The complete
severance process occurs during one trip into the well bore.
[0150] Although this system is designed for precise W-axis movement
in a 360 degree horizontal plane, due to the wide swath or void it
generates when removing material in said horizontal plane, it does
not require the exact alignment of the starting and ending points
in the 360 degree cut that are otherwise required by traditional
waterjet systems. Traditional narrow-kerfs abrasive waterjet
systems often create a "spiral" cut because of an inability to
maintain perfect alignment from the starting point to the ending
point. This "spiral" cut causes severance attempts to fail because
the starting point of the cut and the ending point of the cut did
not meet.
[0151] Additionally, by cutting a void (or swath) into the
tubulars, the severed casing will drop vertically at the surface
platform, providing visual verification of the severance. The reach
of the cutting device is designed to extend beyond the length of
the cutting device to the outermost casing with any number of
additional tubulars inside this outermost casing being extremely
eccentrically positioned. This solves the cutting "reach" problems
that are encountered with saw and mill cutters that cannot extend
beyond the length or diameter of the cutter.
[0152] The programmable computer-controlled, feedback
sensor-actuated rotary milling process will take less time to
complete severance than mechanical blade cutters or existing
abrasive waterjet et cutting. The actively adjusted rotary milling,
profile generation process prevents the impact breakage that
plagues mechanical blade cutters encountering non-concentric,
multiple, nested tubulars. Furthermore, this invention's capability
of being deployed and completing the severance in one trip downhole
provides a significant advantage over prior art.
[0153] Therefore, a technical advantage of the disclosed subject
matter is the complete severing of tubing, pipe, casing and liners,
as well as cement or other material that may be encountered in the
annuli between the tubulars in a single trip down hole.
[0154] Another technical advantage of the disclosed subject matter
is providing visual verification of severance without employing
additional equipment.
[0155] Yet another technical advantage of the disclosed subject
matter is creating a wide void (or swatch) thereby removing
substantial material such that the start point and end point of the
void (or swath) do not have to precisely align for complete
severance.
[0156] An additional technical advantage of the disclosed subject
matter is avoiding repeat trips down hole because of cutter
breakage.
[0157] Another technical advantage of the disclosed subject matter
is efficiently severing non-concentrically (eccentrically) aligned
nested tubulars.
[0158] Yet another technical advantage of the disclosed subject
matter is accomplishing severance in less time and in an
environmentally benign manner.
[0159] Still another technical advantage is providing three axis
real time electronic feedback showing cutter position and severance
progress graphically on the operator's monitor.
[0160] These and other features and advantages will be readily
apparent to those with skill in the art in conjunction with this
disclosure.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0161] For a further understanding of the nature, objects, and
advantages of the present invention, reference should be had to the
following detailed description, read in conjunction with the
following drawings, wherein like reference numerals denote like
elements and wherein:
[0162] FIG. 1 shows a schematic view of a rig which has collapsed
with a wellbore that will be abandoned.
[0163] FIG. 2 shows a plurality of nested tubulars from the
wellbore of FIG. 1.
[0164] FIGS. 3A and 3B are sectional diagrams of one embodiment of
controlled cutting apparatus which can be used in the method and
apparatus.
[0165] FIG. 4 is an enlarged view of the cutting head of the
cutting apparatus of FIG. 1.
[0166] FIG. 4A is a schematic view of the milling bit from the
cutting head of FIG. 4.
[0167] FIG. 5 is a side view of one embodiment of a controlled
cutting apparatus which can be used in the method and apparatus
[0168] FIG. 6 is an enlarged side sectional view of the cutting
head of the cutting apparatus of FIG. 5.
[0169] FIG. 7 is an enlarged front view of the cutting head of the
cutting apparatus of FIG. 5.
[0170] FIG. 8 is an enlarged side view of the cutting head of the
cutting apparatus of FIG. 5, taken from the opposing side as that
shown in FIG. 6.
[0171] FIG. 9 is a schematic view of packer system which can be
used by the cutting apparatus of FIG. 5 (shown in the collapsed or
non-anchored condition)
[0172] FIG. 10 is a schematic view of packer system which can be
used by the cutting apparatus of FIG. 5 (shown in the expanded or
anchored condition)
[0173] FIG. 11 is a schematic view of a vessel lowering the
controlled cutting apparatus of FIG. 5 into a plurality of nested
tubulars to be cut at least a specified depth below the sea
floor.
[0174] FIG. 12 is a schematic front view of the controlled cutting
apparatus of FIG. 11 after being lowered into an anchoring position
for a plurality of nested tubulars of FIG. 1 (only one tubular
shown for clarity) to be cut at least a specified depth below the
sea floor.
[0175] FIG. 13 is a schematic side view of the controlled cutting
apparatus of FIG. 11 after being lowered into an anchoring position
for a plurality of nested tubulars of FIG. 1 (only one tubular
shown for clarity) to be cut at least a specified depth below the
sea floor.
[0176] FIG. 14 is a schematic front view of the controlled cutting
apparatus of FIG. 11 after being lowered into an anchoring position
for a plurality of nested tubulars of FIG. 1 (now with all three of
the tubulars showny) to be cut at least a specified depth below the
sea floor.
[0177] FIG. 15 is a view schematically showing the beginning of the
cut made by the cutting apparatus of FIG. 11 in the first
tubular.
[0178] FIG. 16 is an enlarged view of the cutting head portion of
the cutting apparatus shown in FIG. 15. FIG. 17 is a view
schematically showing the end of the cut made by the cutting
apparatus of FIG. 11 in the first tubular.
[0179] FIG. 18 is an enlarged view of the cutting head portion of
the cutting apparatus shown in FIG. 17.
[0180] FIG. 19 is a view schematically showing the beginning of the
cut made by the cutting apparatus of FIG. 11 in the second tubular,
after having completed the cut in the first tubular.
[0181] FIG. 20 is an enlarged view of the cutting head portion of
the cutting apparatus shown in FIG. 19.
[0182] FIG. 21 is a view schematically showing the end of the cut
made by the cutting apparatus of FIG. 11 in the second tubular,
after having completed the cut in the first tubular.
[0183] FIG. 22 is an enlarged view of the cutting head portion of
the cutting apparatus shown in FIG. 21.
[0184] FIG. 23 is a view schematically showing the cut made by the
cutting apparatus of FIG. 11 in the third tubular, after having
completed the cuts in the first and second tubulars.
[0185] FIG. 24 is an enlarged view of the cutting head portion of
the cutting apparatus shown in FIG. 23.
[0186] FIG. 25 is a view schematically showing the cutting
apparatus of FIG. 11 being pulled up after having completed the
cuts in the first, second, and third tubulars.
[0187] FIG. 26 is an enlarged view of the cutting head portion of
the cutting apparatus shown in FIG. 25.
[0188] FIG. 27 is a schematic view of the three nested tubulars
which were cut by the cutting apparatus of FIG. 11 (where these
tubulars were concentrically positioned).
[0189] FIG. 28 is a schematic view of the three nested tubulars
which were cut by the cutting apparatus of FIG. 11 (where these
tubulars were eccentrically positioned).
[0190] FIG. 29 is a schematic view of the three cut nested tubulars
being pulled out of the well bore so that the well can be properly
abandoned.
[0191] FIG. 30 is a schematic view of one embodiment of a display
which can show in substantially real time a schematic
representation of the cutting head and the cut or cuts made in one
or more nested tubulars, shown in the beginning of a cut of the
first nested tubular.
[0192] FIG. 31 is a schematic view of one embodiment of a display
which can show in substantially real time a schematic
representation of the cutting head and the cut or cuts made in one
or more nested tubulars, shown in the middle of a cut of the first
nested tubular.
[0193] FIG. 32 is a schematic view of one embodiment of a display
which can show in substantially real time a schematic
representation of the cutting head and the cut or cuts made in one
or more nested tubulars, shown in the beginning of a cut of the
second nested tubular, after completing the cut of the first nested
tubular.
[0194] FIG. 33 is a schematic view of one embodiment of a display
which can show in substantially real time a schematic
representation of the cutting head and the cut or cuts made in one
or more nested tubulars, shown in the middle of a cut of the second
nested tubular, after completing the cut of the first nested
tubular.
[0195] FIG. 34 depicts the robotic rotary mill cutter of one
embodiment.
[0196] FIGS. 35A and 35B, depict the upper and lower portions,
respectively, of the robotic rotary mill cutter.
[0197] FIG. 36 depicts an expanded view of an inserted carbide mill
of one embodiment.
[0198] FIG. 37A depicts a top view of multiple casings (tubulars)
that are non-concentric.
[0199] FIG. 37B depicts an isometric view of non-concentric casings
(tubulars).
[0200] FIG. 38A depicts a portion of the robotic rotary mill cutter
as it enters the tubulars.
[0201] FIG. 38B depicts a portion of the robotic rotary mill cutter
as it is severing multiple casings.
[0202] FIGS. 39A and 39B depict the upper and lower portions,
respectively, of an alternative embodiment of the robotic rotary
mill cutter.
[0203] FIGS. 40A, 40B, and 40C depict side view, isometric view,
and a bottom view of an alternative embodiment of a cutting
device.
[0204] FIGS. 41A and 41B depict embodiments of a steady rest
attached to one embodiment of the robotic rotary mill cutter.
DETAILED DESCRIPTION
[0205] Detailed descriptions of one or more preferred embodiments
are provided herein. It is to be understood, however, that the
present invention may be embodied in various forms. Therefore,
specific details disclosed herein are not to be interpreted as
limiting, but rather as a basis for the claims and as a
representative basis for teaching one skilled in the art to employ
the present invention in any appropriate system, structure or
manner.
[0206] FIGS. 3A and 3B are sectional diagrams of one embodiment of
controlled cutting apparatus 100 which can be used in the method
and apparatus 10. FIG. 4 is an enlarged view of the cutting head
1000 of cutting apparatus 100.
[0207] Generally cutting apparatus 100 can comprise body 500,
cutting head 1000, and elongated cutting member 1500. Tool body 500
can support a supporting a drive system that includes a first motor
W-axis drive 600 and a second motor Z-axis drive 300.
[0208] Cutting apparatus 100 can include a reaction member 1800
which is attached to cutting head 1000. Reaction member 1800 can
include a reaction bar having first 1810 and second ends 1820. On
the second end can include a contact member 1830 which preferably
is comprised of a material adequate to hand reaction forces
expected to be encountered by the cutting member 1500 when cutting
tubulars. Contact member 1830 is also preferably comprised of a
material having a relatively small coefficient of friction to
reduce reactional frictional forces on cutting head 1000 when the
cutting head (and connected reaction member 1800) are moved in the
Z axis direction during a cut. The length of reaction member 1800
(e.g., the length between first end 1810 and contact member 1830)
is preferably long enough such that contact member 1830 will be
below the lower end 77 of the cut in the first nested tubular.
[0209] Cutting apparatus 100 can have, operably connected thereto,
a remote control 4000 having a display 4100 from which an operator
can program, initiate, control, and/or override one or more of the
operations/functions of cutting apparatus 100, cutting head 1000,
and/or cutting member 1500. Remote control 4000 can have one or
more controls 190 operatively connected thereto.
[0210] A collar 200 can be attached to body 500 of cutting
apparatus 100. Referring to FIG. 3A, a collar 200 can be used to
attach the umbilical cord, wireline, and other connecting items to
the body of controlled cutting apparatus 100. Collar 200 may be
exchanged to adapt to different size work strings (not shown).
Additionally, collar 200 provides a quick disconnect point in case
emergency removal of controlled cutting apparatus is necessary.
[0211] The anchoring system 1100 can have engaged and non-engaged
conditions (e.g., see expanded packer condition 1110), wherein
during the engaged condition the tool body 500 is anchored relative
to the tubular, and during the non-engaged position the tool body
is not anchored relative to the tubular. After cutting apparatus
100 is lowered to a selected cutting location, an anchoring system,
such as a hydraulic packer 1100, can be energized to anchor body
500 of cutter 100 into well bore 60. Other types of conventionally
available anchoring systems can be used in place of or in addition
to packer 1100. For example expandable and retractable arms can be
used which expand from body 500 to contact the interior of the
innermost nested tubular of a plurality of nested tubulars. An
anchoring system 1100 allows controlled Z and W axis movement of
cutting head 1000 (along with cutting member 1500). An anchoring
system 1100 also allows controlled Y axis movement of cutting
member 1500. An anchoring system also tends minimize harmful
vibrations to cutting member 1500 during cuts.
[0212] Elongated cutting member 1500 (for example, a carbide
cutter) can be mounted to the milling spindle swing arm 1400, and
can be pivoted out in the Y-axis by Y-axis hydraulic cylinder 1600
into the cut of a tubular member.
Controllable Movement in Z-Axis
[0213] Cutting head 1000 can be operably connected to body 500 such
that cutting head 1000 can be controllably moved along a Z-axis.
The cutting head 1000 can be coupled to the second motor drive 300,
wherein the second motor drive 300 causes the cutting head 1000 to
be selectively moved in the Z-axis relative to the tool body
500.
[0214] The Z-axis control unit can comprise Z-axis motor 300 and
controls, drive cylinder 320 having upper and/or lower threaded
areas 322, 324, and driving screw 400. In one embodiment motor 300
is attached to body 500 via mounting plate 350, and motor 300
rotates screw 400. Because screw 400 is threadably connected to
drive cylinder 320 rotation of screw 400 will cause cylinder 320 to
move in the direction of the Z-axis (in the direction of arrow 2010
or arrow 2020 depending on the direction of rotation of screw 400).
Additionally depending on the speed of rotation of screw 400 (along
with the pitch of the threads of screw 400 the speed of movement in
the Z-axis can be controlled).
[0215] Support bracket 370 connects drive cylinder 320 to W-axis
motor 600. W-axis motor 600 is operably connected to cutting head
tube 1010 through transmission 700, coupling 800 and rotary
hydraulic coupling 900. Cutting head tube is connected to cutting
head 1000. Cutting head tube 1010 is slidably connected to body 500
such that cutting head tube can, in the interior space of body 500,
slide in the Z-axis (extending and retracting as desired) along
with rotating in the W-axis relative to body 500. Cutting head 1000
can include elongated cutting member 1500 and Y-axis actuator
1600.
[0216] In one embodiment transmission 700 can be a step down
transmission with a 126:1 ration.
[0217] Telescoping tubing 360 allow, during the extension and
retraction of drive cylinder 320 an extending and retracting
connection for fluid and/or electrical controls and/or sensor data
to for components lower than mounting plate 350.
Controllable Movement about W-Axis
[0218] Cutting head 1000 can be operably connected to body 500 such
that cutting head 1000 can be controllably rotated about a W-axis.
The cutting head 1000 can be coupled to the first motor drive 600,
wherein the first motor drive 600 causes the cutting head 1000 to
be moved in the W-axis of rotation relative to the tool body
500.
Controllable Movement in Y-Axis
[0219] Elongated cutting member 1500 can be operably connected to
cutting head such that cutting member 1500 can be controllably
pivoted about a Y-axis. An arcuate actuator 1600 can be operatively
connected to the spindle housing 1700, the actuator 1600 having
actuator first 1610 and second 1620 end portions, the first end
portion 1610 being mounted to the cutting head 1000 at an
elevational position (at pivot 1612) which is below the first
elevation (at pivot 1412), and at the other of its end portions
1620 being mounted (at pivot 1622) to the spindle housing 1400 at a
position also below the first elevation (at pivot 1412), the
actuator 1600 moving the spindle housing 1400 and elongated cutting
member 1500 between first and second extreme arcuate positions
(FIG. 3B and FIG. 4).
Controllable Movement about Longitudinal Axis of Cutting Member
[0220] Elongated cutting member 1500 can be operably connected to
cutting head 1000 such that cutting member 1500 can be controllably
rotated about an elongated cutting member's 1500 longitudinal axis.
A third motor drive 1220 can be operably connected to the elongated
cutting member 1500 causing the elongated cutting member 1500 to
rotate about the elongated cutting member's longitudinal axis 1514
and relative to the spindle housing 1400. The speed of rotation and
force of rotation can be controlled by motor 1220.
[0221] The cutting head 1000 can include: a spindle housing 1400
pivotally connected to the cutting head 1000 at a pivot 1412, the
pivot 1412 being located at a first elevation, the spindle housing
1400 having:
[0222] (1) an elongated cutting member 1500 with distal 1520 and
proximal ends 1510, and the elongated cutting member 1500 being
rotationally connected to the spindle housing 14, the elongated
cutting member 1500 having a longitudinal axis (axis of rotation
1514) spanning between its first 1510 and second 1520 ends,
[0223] (2) the spindle housing 14 having a second lower distal end
portion 1420 and first upper proximal end portion 1410, the upper
proximal end portion 1410 being connected to the cutting head 1000
at the pivot 1412, the spindle housing 1400 and elongated cutting
member 1500 being able to travel through an arcuate path (Y-axis)
having first and second extreme arcuate positions, wherein the
first extreme arcuate position (FIG. 3B) is more closely aligned
with the Z-axis compared to the second extreme arcuate position
(FIG. 4), and the second extreme arcuate position (FIG. 4) is more
closely aligned with the W-axis compared to the first extreme
arcuate position (FIG. 3B). Arrows 1414 schematically indicating
pivoting about pivot 1412.
[0224] FIG. 4A is a sectional view of the cutting bit 1500
separated from the cutting head 1000. Cutting bit 1500 comprises
body 1505 having first end 1510 and second end 1520. Between first
and second ends are a plurality of teeth 1530 which can spin about
axis of rotation 1514 (arrow 1516 schematically indicating rotation
about axis of rotation 1514, and spinning can occur in the opposite
direction of arrow 1516).
[0225] A vibration reduction system can be included in cutting bit
1500 which can comprise an opening 1508 in body 1505, wherein such
opening 1508 is filled with heavy oil 1580. Cap 1570 can be
threadably connected to body 1505 at second end 1520. Screw 1560
can be threadably connected to body 1505 at first end 1510. Screw
1562 can be threadably connected to cap 1570.
[0226] Spanning opening 1508 can be bar 1540 (which can be kept
under tension between screw 1560 and screw 1560) causing body 1505
of cutting bit 1500 to be kept under compression. Opening. Opening
1508 can be sealed by plunger 1550 having O-ring seals 1585 keeping
heavy oil 1580 in opening 1508. The combination of heavy oil 1508
and tension of bar 1540 assists in reducing vibrations in cutting
bit 1500 during cutting.
[0227] In one embodiment body 1505 can be an alloy steel, bar 1540
can be tungsten, and plunger 1550 and cap 1570 can be aluminum
bronze.
One Embodiment of Method and Apparatus
[0228] Below is included one embodiment of a method for using of
cutting apparatus 100 for severing a plurality of nested tubulars
70 (which can be concentrically or eccentrically nested relative to
each other), each tubular having a tubular bore, the nested
tubulars being disposed in a well bore and wherein there is an
outer tubular and an inner tubular inside the bore of the outer
tubular, method comprising the steps of:
[0229] (a) providing a cutting tool, the cutting tool including:
[0230] (i) a tool body 500 configured to be lowered (such as by
wireline 210) into the tubular bore of the innermost nested
tubular, the tool body 5 having a longitudinal Z-axis, a W-axis of
rotation generally perpendicular to the Z-axis, and an anchoring
system 1100 attached to the tool body, the anchoring system 1100
having engaged and non-engaged conditions (e.g., see expanded
packer condition 1110), wherein during the engaged condition the
tool body 500 is anchored relative to the tubular, and during the
non-engaged position the tool body is not anchored relative to the
tubular; [0231] (ii) the tool body 500 including a cutting head
1000 movably connected to the tool body 500 in both the Z and W
axes, the tool body 500 supporting a drive system that includes a
first motor W-axis drive 600 and a second motor Z-axis drive 300;
[0232] (iii) the cutting head 1000 being coupled to the first motor
drive 600, wherein the first motor drive 600 causing the cutting
head 1000 to be moved in the W-axis of rotation relative to the
tool body 500; [0233] (iv) the cutting head 1000 being coupled to
the second motor drive 300, wherein the second motor drive 300
causing the cutting head 1000 to be moved in the Z-axis relative to
the tool body 500; [0234] (v) the cutting head 1000 including: a
spindle housing 1400 pivotally connected to the cutting head 1000
at a pivot 1412, the pivot 1412 being located at a first elevation,
the spindle housing 1400 having: [0235] (1) an elongated cutting
member 1500 with distal 1520 and proximal ends 1510, and the
elongated cutting member 1500 being rotationally connected to the
spindle housing 14, the elongated cutting member 1500 having a
longitudinal axis (axis of rotation 1514) spanning between its
first 1510 and second 1520 ends, [0236] (2) the spindle housing 14
having a second lower distal end portion 1420 and first upper
proximal end portion 1410, the upper proximal end portion 1410
being connected to the cutting head 1000 at the pivot 1412, the
spindle housing 1400 and elongated cutting member 1500 being able
to travel through an arcuate path (Y-axis) having first and second
extreme arcuate positions, wherein the first extreme arcuate
position (FIG. 3B) is more closely aligned with the Z-axis compared
to the second extreme arcuate position (FIG. 4), and the second
extreme arcuate position (FIG. 4) is more closely aligned with the
W-axis compared to the first extreme arcuate position (FIG. 3B);
[0237] (vi) an arcuate actuator 1600 operatively connected to the
spindle housing 1700, the actuator having 1600 actuator first 1610
and second 1620 end portions, the first end portion 1610 being
mounted to the cutting head 1000 at an elevational position (at
pivot 1612) which is below the first elevation (at pivot 1412), and
at the other of its end portions 1620 being mounted (at pivot 1622)
to the spindle housing 1400 at a position also below the first
elevation (at pivot 1412), the actuator 1600 moving the spindle
housing 1400 and elongated cutting member 1500 between first and
second extreme arcuate positions (FIG. 3B and FIG. 4); and [0238]
(vii) a third motor drive 1220 operably connected to the elongated
cutting member 1500 causing the elongated cutting member 1500 to
rotate about the elongated cutting member's longitudinal axis 1514
and relative to the spindle housing 1400;
[0239] (b) from a surface location lowering the cutting tool into
an innermost tubular of a plurality of nested tubulars;
[0240] (c) the third drive motor 1220 causing the elongated cutting
member 15 to rotate about the rotational cutting axis 1514;
[0241] (d) the actuator 1600 causing the rotational cutting axis
1514 to move between the first and second extreme arcuate angles
(FIGS. 3B and 4 with rod 1640 respectively in retracted and
extended conditions);
[0242] (e) the second drive motor 600 rotating the cutting head
1000 in the W-axis;
[0243] (f) after step "b" and before step "g" the third drive motor
300 moving the cutting head 17 in the Z axis (in the direction of
arrow 380 either upwardly 2010 or downwardly 2020 by turning
driving screw 400 to move driving nut 310); and
[0244] (g) before raising the tool body 500 to the surface location
30, completely severing the plurality of the nested tubulars 70
with the elongated cutting member 1500.
[0245] In the preferred embodiment, after anchoring body 500 of
cutter 100, Z-axis motor 300 causes cutting head 1000 to move in
the direction of arrow 2020 to a down position. Such initial
downward movement of cutting head 1000 permits elongated cutting
member 1500 to begin cutting at the lowest point of the cut (e.g.,
point 77 in tubular 75) and be raised (in the direction of arrow
2010) as needed to cause a depth of cut (e.g., depth 78 in tubular
75) sufficient to allow elongated cutting member 1500 access to
make cuts in the larger nested tubulars (e.g., tubular 80, 85,
etc.) of a plurality of nested tubulars 70.
[0246] FIG. 1 shows a schematic view of a rig 40 which has
collapsed with a wellbore 60 (along with a plurality of nested
tubulars 70) that will be abandoned. Tubular is intended to be
broadly construed to include pipe, tubing, casing, conduit, along
with other cylindrical items that can be installed in a wellbore
60.
[0247] FIG. 2 shows three nested tubulars 75, 80, and 85 of a
plurality of nested tubulars 70 which are to be cut by cutting
apparatus 100 (where these tubulars are concentrically positioned
relative to each other). In various embodiments the tubulars can
have in their annuluses between them combinations of cement and/or
formation rock (although such is not shown in FIG. 2).
[0248] In FIG. 2, riser 50 shown in FIG. 1 has been previously cut
to a height "H" above sea floor 20 by conventionally available
methods (such as wireline) to provide easy access to the interior
of the innermost nested tubular 75. To properly abandon wellbore 60
the plurality of nested tubulars 70 must be cut to a depth D below
sea floor 20 which exceeds regulatory requirements.
[0249] FIGS. 3A and 3B are sectional diagrams of one embodiment of
controlled cutting apparatus 100 which can be used in the method
and apparatus 10.
[0250] FIG. 4 is an enlarged view of the cutting head 1000 of
cutting apparatus 100.
[0251] FIG. 5 is a side view of one embodiment of a controlled
cutting apparatus 100 which can be used in the method and apparatus
10. Cutting apparatus is shown in the state at which it will be
lowered into the innermost nested tubular 75 for a cut. In this
state cutting member 1500 is in its home position or the smallest
Y-axis position (compared to the Z-axis). However, it should be
noted that the home Y-axis position of cutting member 1500 is not
zero degrees. Preferably, this home Y-axis position can 1, 2, 3, 4,
5, 6, 7, 8, 9, or 10 degrees from the Z-axis. In various
embodiments the home Y-axis position can be a range between any two
of the above stated home Y-axis positions. The cutting head is also
shown in the home Z-axis position--where tube 1010 is maximally
retracted into body 500 of cutting apparatus 100. The cutting head
is also shown in the home W-axis which can be an arbitrarily chosen
position in the W-axis because cutting apparatus 1000 will be
lowered on line 210 by vessel 300, and while being lowered, cutting
apparatus 1000 itself can rotate somewhat freely in the W-axis.
After cutting apparatus has been put in the anchored state (such as
by inflation of packer 1100 in tubular 75), relative movement of
cutting head 1000 in the W-axis can be monitored and measured
(i.e., when cutting apparatus is in place and anchored for a cut).
In FIG. 5 hydraulic packer 1100 is shown deflated or in the
non-anchored state.
[0252] FIG. 6 is an enlarged side sectional view of cutting head
1000 of cutting apparatus 100 where cutting member 1100 is shown in
the home or Y-axis retracted state. FIG. 7 is an enlarged front
view of cutting head 1000 of cutting apparatus 100. FIG. 8 is an
enlarged side view of cutting head 1000 of cutting apparatus 100
taken from the opposing side as that shown in FIG. 6. Arrow 1840
schematically indicates reaction force being placed on cutting head
1000 when cutting member 1500 moves out in the Y-axis direction.
Such reaction force will tend to cause the body 500 of cutting
apparatus to pivot about its anchor point (e.g., the place of
anchor by packer 1100) in the direction of arrow 1840. Such
pivoting is limited by contact surface 1830 of reaction member 1800
contacting innermost tubular 75 where such contact will cause an
equal and opposing reaction force to be applied to contact member
1830 and body 500. In this manner reaction member 1800 helps
stabilizing cutting apparatus 100 during a cut.
[0253] FIG. 9 is a schematic view of packer system 1100 which can
be used by cutting apparatus 100 (shown in the collapsed or
non-anchored condition) to place cutting apparatus 100 in anchored
and non-anchored states relative to the innermost nested tubular
75. FIG. 10 is a schematic view of packer system 1100 shown in the
expanded or anchored condition.
[0254] FIG. 11 is a schematic view of a vessel 3000 using crane
3050 to lower (schematically indicated by arrow 110) controlled
cutting apparatus 100 into a plurality of nested tubulars 70 to be
cut at least a specified depth "D" below sea floor 20. This is a
schematic figure and not to scale. An operator can control cutting
apparatus 100 using remote controller 4000, with controller having
a display 4100 for ease of operation.
[0255] FIG. 12 is a schematic front view of controlled cutting
apparatus 100 after being lowered into an anchoring position for
cutting a plurality of nested tubulars 70 (however, for clarity
only one tubular 75 is shown for clarity) to be cut at least a
specified depth "D" below sea floor 20. FIG. 13 is a schematic side
view of controlled cutting apparatus 100 after being lowered into
an anchoring position for cutting a plurality of nested tubulars 70
(however, for clarity only one tubular 75 is shown for clarity) to
be cut at least a specified depth "D" below sea floor 20. FIG. 14
is a schematic front view of controlled cutting apparatus 100 after
being lowered into an anchoring position for cutting a plurality of
nested tubulars 70 (now with all three of the tubulars 75, 80, and
85 shown) to be cut at least a specified depth "D" below the sea
floor 20. In these figures cutting head 1000 is fully retracted and
in the home position in the Z axis (schematically indicated by Zh).
Cutting head 1000 is also in the home position for the W axis; and
cutting member 1500 is in the home position in the Y-axis
[0256] FIGS. 15 through 18 schematically illustrate various steps
using cutting apparatus 100 to make a cut in the first nested
tubular 75 of the plurality of nested tubulars 70.
[0257] FIG. 15 is a view which schematically shows the beginning of
a cut being made by cutting apparatus 100 in first tubular 75. FIG.
16 is an enlarged view of cutting head portion 1000 of cutting
apparatus 100 in the position shown in FIG. 15. In these figures
cutting head 1000 has extended in the Z-axis from the home position
(Zh) to the position to start the first cut (Z1). Also in these
figures cutting member 1500 has pivoted from the home position in
the Y axis to the Y-axis position Y1 to make the first cut
(schematically indicated by Y1). While making the cut cutting
member 1500 will be rotated about its longitudinal axis 1514
(schematically indicated by the arrow about axis 1514) at a
controlled rotational speed. Also while making the cut cutting head
1000 will be rotated in the W-axis at a controlled rotational speed
(schematically indicated by the W-arrow). Also while making this
cut, cutting head 1000 will be pulled up in the direction of arrow
2010 along the Z-axis from Z-axis location Z1 to Z-axis location
Z2. In this manner cutting member 1500 will traverse an upward
helical or spiral pathway cutting a swath in the tubular.
[0258] FIG. 17 is a view schematically showing the end of a cut
being made by cutting apparatus 100 in the first tubular 75. FIG.
18 is an enlarged view of cutting head 1000 portion of cutting
apparatus 100 in the position shown in FIG. 17. While making this
cut, cutting head 1000 was pulled up in the direction of arrow 2010
along the Z-axis from Z-axis location Z1 to Z-axis location Z2
(which is more retracted compared to position Z1). Now a swath or
cut has been made in nested tubular 75 from bottom 77 to top 76
making a gap 78. It is noted that in FIG. 18 length 1850 of
reaction arm 1800 is shown where contact member 1830 loses contact
with tubular 75 as cutting head 1000 is retracted along the Z-axis
(to position Z2). It is preferable that length 1850 is long enough
so that contact member will maintain contact during the retracting
process of the first cut. However, continuous contact of contact
member 1830 may not be as important (compared to tubulars 80, 85,
etc) for cutting the first tubular 75 because the first tubular
will have the smallest diameter and the smallest vibration issues
(compared to larger tubulars 80, 85, etc).
[0259] FIGS. 19 through 22 schematically illustrate various steps
using cutting apparatus 100 to make a cut in the second nested
tubular 80 of the plurality of nested tubulars 70.
[0260] FIG. 19 is a view which schematically showing the beginning
of a cut being made by cutting apparatus 100 in second tubular 80,
after having completed the cut in the first tubular 75 (with a cut
depth 78 in the first tubular 75). FIG. 20 is an enlarged view of
cutting head 1000 portion of cutting apparatus 100 in the position
shown in FIG. 19. In these figures cutting head 1000 has extended
in the Z-axis from the home position (Zh) to the position to start
the first cut (Z3). Also in these figures cutting member 1500 has
pivoted to the Y-axis position Y2 to make the second cut
(schematically indicated by Y2). While making the cut cutting
member 1500 will be rotated about its longitudinal axis 1514
(schematically indicated by the arrow about axis 1514) at a
controlled rotational speed. Also while making the cut cutting head
1000 will be rotated in the W-axis at a controlled rotational speed
(schematically indicated by the W-arrow). Also while making this
cut, cutting head 1000 will be pulled up in the direction of arrow
2010 along the Z-axis from Z-axis location Z3 to Z-axis location
Z4. In this manner cutting member 1500 will traverse an upward
helical or spiral pathway cutting a swath in tubular 80.
[0261] FIG. 21 is a view schematically showing the end of cut being
made by cutting apparatus 100 in the second tubular 80, after
having completed the cut in the first tubular 75 (with a cut depth
78 in the first tubular 75). FIG. 22 is an enlarged view of cutting
head 1000 portion of cutting apparatus 100 in the position shown in
FIG. 21. While making this cut, cutting head 1000 was pulled up in
the direction of arrow 2010 along the Z-axis from Z-axis location
Z3 to Z-axis location Z4 (which is more retracted compared to
position Z3). Now a swath or cut has been made in nested tubular 80
from bottom 82 to top 83 making a gap 84. It is noted that in FIG.
22 length 1850 of reaction arm 1800 is shown where contact member
1830 does not lose contact with tubular 75 as cutting head 1000 is
retracted along the Z-axis (from position Z3 to position Z4).
[0262] FIGS. 23 and 24 schematically illustrate various steps using
cutting apparatus 100 to make a cut in the third tubular 85 of the
plurality of nested tubulars 70.
[0263] FIG. 23 is a view schematically showing a cut being made by
cutting apparatus 100 in the third tubular 85, after having
completed the cuts in the first and second tubulars (with a cut
depth 78 in the first tubular 75, and a cut depth 83 in the second
tubular 80). FIG. 24 is an enlarged view of cutting head 1000
portion of cutting apparatus 100 in the position shown in the FIG.
23. In these figures cutting head 1000 has extended in the Z-axis
from the home position (Zh) to the position to start the first cut
(Z5). Also in these figures cutting member 1500 has pivoted to the
Y-axis position Y3 to make the second cut (schematically indicated
by arrow Y3). While making the cut cutting member 1500 will be
rotated about its longitudinal axis 1514 (schematically indicated
by the arrow about axis 1514) at a controlled rotational speed.
Also while making the cut cutting head 1000 will be rotated in the
W-axis at a controlled rotational speed (schematically indicated by
the W-arrow). Also while making this cut, in one embodiment,
cutting head 1000 will be pulled up in the direction of arrow 2010
along the Z-axis from Z-axis location Z5 to Z-axis location Z6. In
this manner cutting member 1500 will traverse an upward helical or
spiral pathway cutting a swath in tubular 85. In one embodiment
cutting head 1000 is maintained at a constant position Z5 and
cutting member 1500 makes a cut through tubular 85 (and no spiral
motion is seen by cutting member 1500).
[0264] FIG. 25 is a view schematically showing cutting apparatus
1000 being pulled up (schematically indicated by arrow 2010) after
having completed the cuts in the first 75, second 80, and third 85
tubulars--completely severing the plurality of nested tubulars 70
(with a cut depth 78 in the first tubular 75, a cut depth 83 in the
second tubular 80, and a cut depth 87 in the third tubular 85).
FIG. 26 is an enlarged view of cutting head 1000 portion of cutting
apparatus 100 in the position shown in FIG. 25. The upper portions
of the plurality of the plurality of nested tubulars 70 now ready
to be pulled out of wellbore 60. In these figures cutting head 1000
has been retracted to its home position in the Z-axis (to Zh), and
cutting member 1500 has also been pivoted in the Y-axis to its home
position. Additionally, hydraulic packer 1100 has been released
causing cutting apparatus to enter a non-anchored state. Cutting
apparatus 100 is now in a condition to be pulled up by vessel 3000
in the direction of arrow 2010 to the surface.
[0265] In one embodiment from the beginning of the cut of the first
tubular 75 to the completion of the cut of the outermost tubular
85, cutting apparatus remained below the surface of the water 30.
In one embodiment, during this time cutting apparatus remained in
well bore 60. In one embodiment, cutting apparatus remained
anchored in a single position in innermost tubular 75.
Concentric Tubulars
[0266] FIG. 27 is a schematic view of the three nested tubulars 75,
80, and 85 of a plurality of nested tubulars 70 which were cut by
cutting apparatus 100 (where these tubulars were concentrically
positioned). In various embodiments the tubulars can have in their
annuluses between them combinations of cement and/or formation
rock.
[0267] Tubular 75 cut has upper level 76 and lower level 77, with a
height or swath of cut 78. Tubular 80 cut has upper level 81 and
lower level 82, with a height or swath of cut 83. Tubular 85 cut
has upper level 86 and lower level 87, with a height or swath of
cut 88.
[0268] In one embodiment height of cut 78 is larger than height of
cut 83, and height of cut 83 is larger than height of cut 88. In
one embodiment lower level 77 is lower than lower level 83, and
lower level 83 is lower than lower level 87. In one embodiment
upper level 76 is higher than upper level 81, and upper level 81 is
higher than upper level 86. In one embodiment lower level 77 is
equal to lower level 83, and lower level 83 is equal to lower level
87.
[0269] In one embodiment height of cut 78 is larger than height of
cut 83, and height of cut 83 is larger than height of cut 88. In
one embodiment lower level 77 is lower than lower level 83, and
lower level 83 is lower than lower level 87. In one embodiment
upper level 76 is higher than upper level 81, and upper level 81 is
higher than upper level 86.
[0270] In one embodiment lower level 77 is about equal to lower
level 83, and lower level 83 is about equal to lower level 87 (and
Z1 is about equal to Z3 and Z3 is about equal to Z5).
Eccentric Tubulars
[0271] FIG. 28 is a schematic view of the three nested tubulars 75,
80, and 85 of a plurality of nested tubulars 70 which were cut by
cutting apparatus 100 (where these tubulars were eccentrically
positioned). In various embodiments the tubulars can have in their
annuluses between them combinations of cement and/or formation
rock. In various embodiments the tubulars can have in their
annuluses between them combinations of cement and/or formation
rock.
[0272] Tubular 75 cut has upper level 76 and lower level 77, with a
height or swath of cut 78. Tubular 75 cut also has upper level 76'
and lower level 77', with a height or swath of cut 78'. Tubular 80
cut has upper level 81 and lower level 82, with a height or swath
of cut 83. Tubular 80 cut also has upper level 81' and lower level
82', with a height or swath of cut 83'. Tubular 85 cut has upper
level 86 and lower level 87, with a height or swath of cut 88.
Tubular 85 cut also has upper level 86' and lower level 87', with a
height or swath of cut 88'. In one embodiment height of cut 78 is
larger than height of cut 83, and height of cut 83 is larger than
height of cut 88. In one embodiment height of cut 78' is larger
than height of cut 83', and height of cut 83' is larger than height
of cut 88'. In one embodiment lower level 77 is lower than lower
level 83, and lower level 83 is lower than lower level 87. In one
embodiment lower level 77' is lower than lower level 83', and lower
level 83' is lower than lower level 87'. In one embodiment upper
level 76 is higher than upper level 81, and upper level 81 is
higher than upper level 86. In one embodiment upper level 76' is
higher than upper level 81', and upper level 81' is higher than
upper level 86'. In one embodiment lower level 77 is equal to lower
level 83, and lower level 83 is equal to lower level 87. In one
embodiment lower level 77' is equal to lower level 83', and lower
level 83' is equal to lower level 87'.
[0273] FIG. 29 is a schematic view of the upper portions 75', 80',
and 85' of the three cut nested tubulars 70 being pulled out of
well bore 60 so that the wellbore can be properly abandoned. Now
from the sea floor 20 to the top of the remaining plurality of
nested tubulars 70 is at least a depth D.
[0274] FIG. 30 is a schematic view of one embodiment of a display
4100 showing (in substantially real time) a schematic
representation of relative movement of the cutting head 1000 and
the cut or cuts made in one or more nested tubulars of a plurality
of nested tubulars 70, shown in the beginning of a cut of the first
nested tubular 75. FIG. 31 is a schematic view of one embodiment of
a display 4100 showing (in substantially real time) a schematic
representation of relative movement of the cutting head 1000 and
the cut or cuts made in one or more nested tubulars of a plurality
of nested tubulars 70, shown in the middle of a cut of the first
nested tubular 75.
Estimated Sample Times and W-Axis Times for Cuts
[0275] Below are provided some sample estimated cutting times and
number of W-axis rotations required for cutting particular sized
nested tubulars with the method and apparatus.
TABLE-US-00001 TABLE 1 SAMPLE OF ESTIMATED CUTTING PROFILES/TIMES
TWO TUBULARS 1.sup.st size W-REV 2.sup.nd SIZE W-REV TOTAL W-REV
EST. TIME 95/8'' 7 135/8'' 1 8 4 MIN 95/8'' 16 24'' 1 17 9 MIN
95/8'' 18 30'' 1 19 10 MIN
TABLE-US-00002 TABLE 2 SAMPLE OF ESTIMATED CUTTING PROFILES/TIMES 3
TUBULARS 1.sup.st SIZE/ 2.sup.nd SIZE/ 3.sup.rd SIZE/ EST. W-REV
W-REV W-REV TOTAL TIME 95/8''/12 133/8'''/6 20''/1 19 10 MIN
[0276] In one embodiment cutter 100 has tool body 500 pressurized
with nitrogen with the advantage of pressurization is that changes
in temperature in the well formation do not create condensation
inside the tool body while the tool is inside the well
formation.
[0277] In one embodiment, how far in the Z-axis (Z1) cutting head
1000 goes down depends on the outer diameter of the outermost
nested tubular to be cut.
[0278] In one embodiment the rate of feed in the Z-axis is equal to
2 inches per revolution of the cutting head in the W-axis- or 2
inches per W axis revolution.
Display for Cut of Innermost Tubular
[0279] Looking at FIGS. 31 and 32 an operator can have a pictorial
representation on display 4100 viewing a three dimensional the
graphical depiction of the cut being made, along with the relative
movements of cutting head 1000 and cutting member 1500 about the Y,
Z, and W axes on such display. One can also visualize the swath or
cut made in the innermost nested tubular 75 having a gap 78'. FIG.
31 shows cutting head 1000 and cutting member 1500 in a second
position for W and Z axes (the Y-axis position remained the same).
FIG. 31 also schematically depicts the cut made in tubular 75 from
the position shown in FIG. 30 to the position shown in FIG. 31. The
relative Y, Z, and W axial positions of cutting head 1000 and
cutting member 1500 can be obtained from sensor and positional
information and/or data from cutting apparatus 100.
Display for Cut of Second Tubular
[0280] FIG. 32 is a schematic view of one embodiment of a display
4100 showing (in substantially real time) a schematic
representation of relative movement of the cutting head 1000 and
the cut or cuts made in one or more nested tubulars of a plurality
of nested tubulars 70, shown in the beginning of a cut of the
second nested tubular 80, after completing the cut of the first
nested tubular 75. FIG. 33 is a schematic view of one embodiment of
a display 4100 showing (in substantially real time) a schematic
representation of relative movement of the cutting head 1000 and
the cut or cuts made in one or more nested tubulars of a plurality
of nested tubulars 70, shown in the middle of a cut of the second
nested tubular 80, after completing the cut of the first nested
tubular 75.
[0281] Looking at FIGS. 32 and 33 an operator can have a pictorial
representation on display 4100 viewing a three dimensional the
graphical depiction of cut being made in the second tubular 80
(along with the cut already made in the first tubular 75), along
with the relative movements of cutting head 1000 and cutting member
1500 about the Y, Z, and W axes on such display. The operator can
also see the swath or cut made in the second tubular 80 having a
gap 81'. FIG. 33 shows cutting head 1000 and cutting member 1500 in
a second position for W and Z axes (the Y-axis position remained
the same Y2). FIG. 33 also schematically depicts the cut made in
tubular 80 from the position shown in FIG. 32 to the position shown
in FIG. 33 (along with the completed cut in the innermost tubular
75). The relative Y, Z, and W axial positions of cutting head 1000
and cutting member 1500 can be obtained from sensor and positional
information and/or data from cutting apparatus 100.
[0282] Viewing of cuts in third, fourth, etc. tubulars can
similarly be displayed on display 4100 of controller 4000. For
example, with three nested tubulars 75, 80, and 85, a cut (cut or
swath 87') in the third tubular 85 could be displayed on display
4100 with swaths or cuts already shown for the first and second
tubulars (first tubular having completed swath or cut 78 and second
tubular having completed watch or cut 83).
[0283] The following is a table listing the various reference
numerals used in this application and a description of each. Note
that this table describes only the reference numerals for FIGS. 1
through 33. In later figures, similar or identical parts may be
identified by different numerals.
TABLE-US-00003 TABLE OF REFERENCE NUMERALS AND DESCRIPTIONS
Reference Description 10 method and apparatus 20 sea floor 30 water
surface 40 oil and gas rig 44 collapsed portion 48 remaining
support structure 50 riser 60 well bore 70 plurality of nested
tubulars 75 first tubular 76 upper portion 77 lower portion 78
height of cut 80 second tubular 81 upper portion 82 lower portion
83 height of cut 85 third tubular 86 upper portion 87 lower portion
88 height of cut 100 apparatus 110 arrow 190 controls 200 collar
210 wireline 300 Z-axis motor and controls 310 driving nut 320
drive cylinder 350 mounting plate or bracket for Z-axis motor 360
telescoping tubing 370 support bracket 380 vertical arrows 400
driving screw 500 tool body or housing 510 interior space 600
W-axis motor 700 transmission system 800 coupling 900 rotary
hydraulic coupling 1000 cutting head (connected to W-axis rotating
body and Z-axis movable bar) 1010 cutting head tube 1100 packer
(for anchoring system) 1110 packer in expanded condition 1120
expanding arrows 1130 connection point for packer 1200 milling
spindle swing arm 1220 motor for cutting bit 1300 pivot bearing
1400 milling spindle swing arm housing 1404 wall 1410 first end
1412 pivot point 1420 second end 1424 arrows 1500 cutting bit 1505
body 1508 opening or bore 1510 first end 1514 axis of rotation 1516
arrow schematically indicating rotation about axis of rotation 1520
second end 1530 milling bit teeth 1540 bar (under tension) 1550
plunger 1560 socket head cap screw 1562 socket head cap screw 1570
cap 1580 heavy oil 1585 O-ring seals 1600 Y axis hydraulic cylinder
1610 first end 1612 pivot point 1620 second end 1622 pivot point
1630 cylinder 1634 arrows schematically indicating ability to pivot
1640 rod 1644 arrows schematically indicating the ability to extend
and retract 1700 connection housing to W-axis rotating body 1710
first end 1720 second end 1800 reaction bar 1810 first end 1820
second end 1830 contact surface 1840 reaction bending force arrow
2000 step of lowering 3000 vessel 3010 surface of vessel 3020
control area 3050 crane 4000 remote controller 4100 display H
height above sea floor D depth of cut below sea floor
[0284] All measurements disclosed herein are at standard
temperature and pressure, at sea level on Earth, unless indicated
otherwise. All materials used or intended to be used in a human
being are biocompatible, unless indicated otherwise.
[0285] It will be understood that each of the elements described
above, or two or more together may also find a useful application
in other types of methods differing from the type described above.
Without further analysis, the foregoing will so fully reveal the
gist of the present invention that others can, by applying current
knowledge, readily adapt it for various applications without
omitting features that, from the standpoint of prior art, fairly
constitute essential characteristics of the generic or specific
aspects of this invention set forth in the appended claims. The
foregoing embodiments are presented by way of example only; the
scope of the present invention is to be limited only by the
following claims.
[0286] Although described with reference to specific embodiments,
one skilled in the art could apply the principles discussed herein
to other areas and/or embodiments.
[0287] Throughout this disclosure casing(s) and tubular(s) are used
interchangeably.
[0288] This invention provides a method and apparatus for
efficiently severing installed tubing, pipe, casing, and liners, as
well as cement or other encountered material in the annuli between
the tubulars, in one trip into a well bore.
[0289] Reference will now be made in detail to the present
embodiments of the disclosure, examples of which are illustrated in
the accompanying drawings. Wherever possible, the same reference
numbers will be used throughout the drawings to refer to the same
or like parts (elements).
[0290] To help understand the advantages of this disclosure the
accompanying drawings will be described with additional specificity
and detail.
[0291] The method generally is comprised of the steps of
positioning a robotic rotary mill cutter inside the innermost
tubular in a pre-selected tubular or plurality of multiple, nested
tubulars to be cut, simultaneously moving the rotary mill cutter in
a predetermined programmed vertical X-axis, and also 360 degree
horizontal rotary W-axis, as well as the spindle swing arm in a
pivotal Y-axis arc.
[0292] In one embodiment of the present disclosure the vertical (Z
axis) and horizontal (W axis) movement pattern(s) and the spindle
swing arm (Y axis) are capable of being performed independently of
each other, or programmed and operated simultaneously in
conjunction with each other. The robotic rotary mill cutter is
directed and coordinated such that the predetermined pattern is cut
through the innermost tubular beginning on the surface of said
tubular, with the cut proceeding through it to form a shape or
window profile(s), or to cut through all installed multiple, nested
tubulars into the formation beyond the outermost tubular by making
multiple passes and cutting away layer by layer of tubulars and
cement until the largest (outermost) nested tubular has been
severed.
[0293] In one embodiment of the present disclosure the robotic
rotary mill cutter, will cut from the inside of a 8.5 inch tubular
and cut away layer by layer nested tubulars and cement thus
generating larger and larger voids, that will allow the Y-axis
milling spindle swing arm (see 5014 of FIG. 39B) and cutting device
(see 5015 of FIG. 39B) progressively greater swing angles and
reach. In three to four passes of cutting away layer by layer of
nested tubulars (see FIG. 38B) and cement as above, the cutting
device 5015 can cut away tubulars and cement inside a 42-inch
diameter circle.
[0294] A profile generation system simultaneously moves the robotic
rotary mill cutter in a vertical Z-axis, and a 360-degree
horizontal rotary W-axis, and the milling spindle swing arm (see
5014 of FIG. 39B) in a pivotal Y-axis arc to allow cutting the
tubulars, cement, and formation rock in any programmed shape or
window profile(s).
[0295] The robotic rotary mill cutter apparatus is programmable to
simultaneously or independently provide vertical X-axis movement,
360-degree horizontal rotary W-axis movement, and spindle swing arm
pivotal Y-axis arc movement under computer control. A computer
having a memory and operating pursuant to attendant software,
stores shape or window profile(s) templates for cutting and is also
capable of accepting inputs via a graphical user interface, thereby
providing a system to program new shape or window profile(s) based
on user criteria. The memory of the computer can be one or more of
but not limited to RAM memory, flash memory, ROM memory, EPROM
memory, EEPROM memory, registers, hard disk, a removable disk, a
CD-ROM, floppy disk, DVD-R, CD-R disk or any other form of storage
medium known in the art. In the alternative, the storage medium may
be integral to the processor. The processor and the storage medium
may reside in an ASIC or microchip.
[0296] The computer controls the profile generation servo drive
systems as well as the cutting device speed. The robotic rotary
mill cutter requires load data to be able to adjust for conditions
that cannot be seen by the operator. The computer receives
information from torque sensors (see 5052, and 5053 of FIGS. 35A
and 35B) attached to Z-axis, W-axis, Y-axis, and milling spindle
drive motor, and makes immediate adaptive adjustments to the feed
rate and speed of the vertical Z-axis, the 360 degree horizontal
rotary W-axis, the spindle swing arm pivotal Y-axis and the RPM of
the milling spindle motor.
[0297] Software in communication with sub-programs gathering
information from the torque devices, such as a GSE model Bi-Axial
transducer Model 6015 or a PCB model 208-M133, directs the
computer, which in turns communicates with and monitors the
downhole robotic rotary mill cutter and its attendant components,
and provides feeds and speeds simultaneously or independently along
the vertical Z-axis, the 360 degree horizontal rotary W-axis, as
well as the pivotal spindle swing arm Y-axis arc movement.
[0298] The shape or window profile(s) are programmed by the
operator using a program logic controller (PLC), or a personal
computer (PC), or a computer system designed or adapted for this
specific use. The integrated software via a graphical user
interface (GUI) or touch screen, such as a Red Lion G3 Series HMI,
accepts inputs from the operator and provides the working
parameters and environment by which the computer directs and
monitors the robotic rotary mill cutter.
[0299] In the preferred embodiment, the vertical Z-axis
longitudinal computer-controlled servo axis uses a hydraulic
cylinder, such as the Parker Series 2HX hydraulic cylinder, housing
the MTS model M-series absolute analog sensor for ease of vertical
Z-axis longitudinal movements, although other methods may be
employed to provide up and down vertical movement of the robotic
rotary mill cutter.
[0300] In a still further embodiment of the present disclosure the
vertical Z-axis longitudinal computer-controlled servo axis may be
moved with a ball screw and a computer controlled electric servo
axis motor, the Fanuc D2100/150 servo, with encoder feedback to the
computer system by an encoder (see 5050 in FIG. 35A) such as the
BEI model H25D series incremental optical encoder. Servomotors and
ball screws are known in the art and are widely available from many
sources.
[0301] In a still further embodiment of the present disclosure the
vertical Z-axis longitudinal computer-controlled servo axis may be
moved with a ball screw and a hydraulic motor, such as a Parker
TC0045, with encoder feedback to a motion controller, similar to a
Galil DMC-21X3 series motion controller, that operates a hydraulic
servo valve, similar to a Parker Series DY12 servovalve, or
hydraulic proportional valve, that powers the hydraulic motor.
Servo valves, proportional valves, and motion controllers are known
in the art and are widely available from many sources.
[0302] In a still further embodiment of the present disclosure, the
vertical Z-axis longitudinal computer-controlled servo axis may be
moved with a rack and pinion, either electrically or hydraulically
driven. Rack and pinion drives are known in the art and are widely
available from many sources.
[0303] In the preferred embodiment, the rotational computer
controlled W-axis rotational movement is an electric servomotor,
The rotational computer-controlled W-axis servomotor, such as a
Fanuc model D2100/150 servo, provides 360-degree horizontal
rotational movement of the robotic rotary mill cutter through a
specially manufactured slewing gear.
[0304] In a still further embodiment of the present disclosure, the
rotational computer controlled W-axis rotational movement is
controlled by a hydraulic servo valve that drives a hydraulic motor
coupled to the W-axis and has a sensor position feedback encoder
connected to the rotational computer controller for closed loop
servo operation.
[0305] Closed loop servo hydraulic drives are a known art and are
widely available from many sources.
[0306] Also in the preferred embodiment, the Y-axis pivotal milling
spindle swing arm computer-controlled servo axis uses a hydraulic
cylinder for ease of use, although other methods may be employed.
The Y-axis pivotal milling spindle swing arm computer-controlled
servo axis, may utilize the Parker Series 2HX hydraulic cylinder,
housing the MTS model M-series absolute analog sensor (see 5051 in
FIG. 35B) inside the hydraulic cylinder to provide position
feedback to the computer controller for pivotal spindle swing arm
Y-axis arc movement.
[0307] In a still further embodiment of the present disclosure an
inertia reference system such as, Clymer Technologies model
Terrella6 v2, can provide information that the robotic rotary mill
cutter is actually performing the movements sent by the computer
controller as a verification reference. The Clymer Technologies
model Terrella6 v2 is mounted in the milling spindle swing arm (see
5014 in FIG. 39B) and provides temperature and vibration monitoring
to the operators display monitor in real time where that
information will be used by the operator to make feed and speed
adjustments for best cutting operations. If the reference shows a
sudden stop, or any axis is not responding to the programmed feeds
and speeds the computer can go into a hold action stopping the
robotic rotary mill cutter and requiring operator intervention
before resuming milling operations. Alarms may be visually shown on
the operator's monitor and/or may have an audible warning.
[0308] The methods and systems described herein are not limited to
specific sizes, shapes, or models. Numerous objects and advantages
of the disclosure will become apparent as the following detailed
description of the multiple embodiments of the apparatus and
methods of the present disclosure are depicted in conjunction with
the drawings and examples, which illustrate such embodiments.
[0309] FIG. 34 depicts the robotic rotary mill cutter 5001. The
robotic rotary mill cutter 5001, shows the position of the vertical
Z-axis, and the 360-degree horizontal rotary W-axis, and the Y-axis
pivotal milling spindle swing arm.
[0310] FIGS. 35A and 35B, depict the upper and lower portions,
respectively, of the robotic rotary mill cutter of the preferred
embodiment.
[0311] Referring to FIG. 35A, a collar 5002 is used to attach the
umbilical cord (not shown) and cable (not shown) to the body of
robotic rotary mill cutter 5001. Collar 5002 may be exchanged to
adapt to different size work strings (not shown). Additionally, the
collar 5002 provides a quick disconnect point in case emergency
removal of the robotic rotary mill cutter 5001 is necessary. In one
embodiment, the collar 5002 may be a spring centralizer about three
feet long. After the robotic rotary mill cutter 5001 is in the cut
location, locking hydraulic cylinders 5003 are energized to lock
the robotic rotary mill cutter 5001 into the well bore (not shown).
In the preferred embodiment, after the locking hydraulic cylinders
5003 have been energized, Z-axis hydraulic cylinder 5006 is moved
to a down position by extending piston rod 5004 allowing the Z-axis
slide 5005 to extend. This permits the robotic rotary mill cutter
5001 to begin cutting at the lowest point of the cut and be raised
as needed to complete the severance.
[0312] Referring to FIG. 35B, additional locking hydraulic
cylinders 5007 are available should additional stabilization (if
energized) or movement (if not energized) is desired. W-axis
servomotor 5008 rotates the W-axis rotating body 5010 under control
of the computer (not shown). W-axis rotating body 5010 houses the
milling spindle swing arm 5014 and the milling spindle swing arm
5014 is driven by motor 5011 also housed in the W-axis rotating
body 5010. Milling spindle swing arm 5014 is driven by motor 5011
through a half-shaft 5012 such as Motorcraft model
6L2Z-3A427-AA.
[0313] Half-shaft 5012 has a C.V. joint (not shown) that allows
milling spindle swing arm 5014 to pivot in an arc from pivot
bearing 5013 that goes through W-axis rotating body 5010. Milling
spindle swing arm 5014 is moved by Y-axis hydraulic cylinder 5016.
The rotation of W-axis rotating body 5010 requires a swivel joint
5009, such as Rotary Systems, Inc. Model DOXX multiple-passage
rotary union, to allow power and sense lines (not shown) to motor
5011, Y-axis hydraulic cylinder 5016, and load cell 5054 sense
wires (not shown). Cutting device 5015 (for example, carbide
milling cutter or solid carbide cutter) is mounted to the milling
spindle swing arm 5014 and is moved by Y-axis hydraulic cylinder
5016 into the cut under computer control.
[0314] FIG. 36 depicts an expanded view of one embodiment of an
inserted carbide mill 5017 that could be attached to milling
spindle swing arm 5014. Other milling units with different material
and/or cutting orientation could be utilized depending on the
particular characteristics of the severance to be performed.
[0315] FIG. 37A depicts a top view of nested multiple casings
(tubulars) 5018 that are positioned non-concentrically.
[0316] FIG. 37B depicts an isometric view of nested multiple
casings (tubulars) 5018 that are positioned non-concentrically.
[0317] FIG. 38A depicts a portion of the robotic rotary mill cutter
5001 as it enters the nested multiple casings (tubulars) 5018.
[0318] FIG. 38B shows the nested multiple casings (tubulars) 5018
with the void that has been created by the robotic rotary mill
cutter 5001. The profile generation system (not shown)
simultaneously moved the robotic rotary mill cutter 5001 in a
vertical Z-axis, and a 360-degree horizontal rotary W-axis, and the
milling spindle swing arm 5014 in a pivotal Y-axis arc to allow
cutting of the tubulars, cement (not shown), and formation rock
(not shown) in any programmed shape or window profile(s) thereby
cutting through the multiple casing (tubulars) 5018, cement (not
shown) or other encountered material in casing annuli (not shown)
by making multiple successfully larger voids created by the robotic
mill cutter as above.
[0319] FIGS. 39A and 39B depict the upper and lower portions,
respectively, of an alternative embodiment of the robotic rotary
mill cutter. Referring first to FIG. 39A, the Z-axis motor 5060
rotates the ball screw 5062 through the Z-axis nut 5064, which
raises or lowers the remainder of the tool. A trombone slide 5066
resides on either side of the ball screw 5062. The trombone slide
5066 is hollow and carries pressured hydraulic fluid to the
remainder of the tool. The trombone slide 5066 is capable of
containing and transmitting hydraulic fluid pressurized to around
1,000 lbs/in.sup.2. The W-axis hydraulic motor drives rotation
about the Z-axis (W-axis rotation). Anti-torque rails (not shown)
stop the tool from rotating when the ball screw 5062 is rotated.
Additionally, tie rods 5068 provide support for the W-axis
transmission 5070.
[0320] The W-axis transmission 5070 rotates the drive bar 5076
within the packer 5078 thereby providing rotation about the Z-axis
(W-axis rotation). In one embodiment, a transmission is employed.
In one embodiment, the transmission is a cluster gear transmission.
The transmission is used because of the size and power constraints
(e.g. relatively small size and relatively high power).
Additionally, in one embodiment, the hydraulic fluid is returned
through the W-Axis transmission for lubrication of the transmission
5070. The shaft coupling 5072 couples the W-axis transmission 5070
to the rotary coupling 5074 that couples to the drive bar 5076. The
rotary coupling 5074 also provides a path for the hydraulic fluid
to pass to the remainder of the tool. In one embodiment, the space
between the drive bar 5076 and the packer 5078 is filled with
pressurized hydraulic fluid (up to around 1,000 lbs/in.sup.2). This
hydraulic fluid acts as an anti-vibration device. Bearings may also
be employed between the drive bar 5076 and the packer 5078 to
reduce vibration and center the drive bar 5076. The packer 5078 can
be fitted with additional bushings (not shown) to accommodate
different size tubulars. Furthermore, the packer 5078, when
pressurized expands/inflates against the wellbore to provide
additional stability and vibration reduction. Additionally, for
larger wellbores, a spacer or sleeve can be attached about the tool
(relatively near the packer) to act a centralizer until the packer
has expanded/inflated to impact the innermost tubular. In yet
another embodiment, a spacer or sleeve could even be placed about
the packer to more closely match the inner diameter of a wellbore
before expanding/inflating the packer.
[0321] Occasionally a tear or other obstruction or flow anomaly may
occur in the fluid delivery lines of a downhole cutter.
Traditionally, the level of a large fluid tank, for example
hydraulic fluid, would be monitored. If the level started
decreasing, then the operators knew there was a problem.
Unfortunately, this routinely occurs only after some significant
amount of fluid is lost downhole (e.g. 20-30 gallons). Furthermore,
the operators only know there is a problem but; they have no idea
which hose had the leak.
[0322] Contrary to traditional models, in addition to the
traditional "level" monitoring, each hose to and from the tool is
fitted with turbine flow meters to continuously monitor the flow of
fluid through each hose. This provides a very early warning system
to alert operators to any flow anomalies. For example, should a
hose develop a tear and begin leaking fluid into the wellbore, the
"delivery" hose would have a flow rate in excess of the "return"
hose. If the difference in the flow meters exceeded a defined
threshold, an operator could be alerted. This is an improvement
over traditional fluid "level" monitoring which could only detect
tears after a significant amount of fluid was lost downhole,
wasting money and creating potential environmental hazards.
Further, traditional "level" monitoring could only detect flow
anomalies that resulted in the loss of fluid. By utilizing turbine
flow meters, pinched, partially blocked/clogged, and/or completely
blocked/clogged hoses can be detected. Also, because each hose has
its own turbine flow meter, the operator can immediately identify
which hose is having the flow anomaly and how serious the flow
anomaly is.
[0323] The spindle housing 5080 is rigidly attached to the drive
bar 5076 such that as the drive bar 5076 rotates, the spindle
housing 5080 also rotates in the W-axis (about the Z-axis). This
rotation can occur while the drive bar 76 is moved longitudinally
(up and down along the Z-axis) by the action of the ball screw
5062. The spindle hydraulic motor 5082 rotates the shaft 5084 and
the cutting device 5015. Although indicated as separate items, in
one embodiment the shaft 5084 and the cutting device 5015 are made
from the same piece of material. This provides the advantage of
increased strength and vibration reduction with no connections
between the shaft 5084 and the cutting device 5015. Finally, the
Y-axis hydraulic cylinder 5016 swings the cutting device 5015 away
from the spindle housing 5080.
[0324] In one embodiment the ratio of shaft 5084 length to cutting
device 5015 length is 1:1 to increase the strength of the assembly
and reduce vibrations. In another embodiment, the cutting device
5015 may swing away from the spindle housing 5080 to an angle of 45
degrees (measured from the vertical center line of the spindle
housing 5080 to the center line of the cutting device 5015) by the
extension of the hydraulic cylinder 5016; however a wider angle is
also achievable.
[0325] Additionally, in one embodiment, a pressure relief hose (not
shown) is attached to the Y-axis hydraulic cylinder 5016. This
pressure relief hose has a valve (not shown) located at the surface
that when actuated releases the pressure from the Y-axis hydraulic
cylinder 5016. This could be used for example to allow the cutting
device 5015 to retract back (see FIG. 39B) within the spindle
housing 5080 should a hydraulic or electrical failure occur while
the tool is deployed downhole and cutting. Without such a failsafe
pressure relief, if the tool failed while cutting, the cutting
device 5015 could be extended so far into the formation as to
interfere with tool recovery. The pressure relief hose and valve
are independent of any electronics on the tool itself or within the
wellbore; therefore, a failure on the tool itself will not
interfere with the failsafe pressure relief because it is
controlled solely from the surface. Another such independent
pressure relief hose (not shown) and valve (not shown) is attached
to the packer for similar reasons.
[0326] In one embodiment, the Y-axis hydraulic cylinder 5016 is
capable of providing over 10,000 lbs of force.
[0327] FIGS. 40A, 40B, and 40C depict side view, isometric view,
and a bottom view of an alternative embodiment of the cutting
device 5015. The shaft 5084 has notches 5100 to enable a sensor
(e.g. proximity switch) to monitor the cutting device's 5015
rotational speed. The cutting device of this embodiment has 84
milling inserts 5104 (although alternate numbers of milling inserts
5104 could be used with success). In this particular embodiment,
the milling inserts 5104 are arranged in 6 rows of 14; however,
alternative configurations could be used with success. Each of the
milling inserts 5104 are mounted on individual insert faces 5106
and are removable in case of breakage or wear. The milling inserts
5104 extend partially above the insert faces 5106 to mill away the
material being cut.
[0328] Each milling insert 5104 has a life expectancy of about 15
minutes of cutting. By careful technique and using a milling insert
5104 layout and number similar to that disclosed herein, one can
make the milling inserts last on the cutting device 5015 for about
two hours of cutting (e.g. each milling insert 5104 sees less than
15 minutes of actual cut time during a two hour cutting episode).
It is important to note that milling through the steel tubulars
degrades the milling inserts 5104; therefore, to maximize cutting
potential, the cutting of the steel tubulars is apportioned across
the entire cutting device 5015.
[0329] This technique of spreading the tubular cutting across the
entire cutting device 5015 is accomplished by making the first cut
only using the lower most milling inserts 5104 of the cutting
device 5015 for a short period of time by feeding the cutting
device 5015 out with hydraulic cylinder 5016 completely through the
innermost tubular. Once the cutting device 5015 is through the
innermost tubular, the spindle housing 5080 is rotated 360-degrees
severing the first tubular. After the first tubular is severed, the
spindle housing 5080 is raised vertically up the Z-axis while
simultaneously rotating in the W-axis to spiral mill cut the
innermost tubular the height required to remove the innermost
tubular. For example, this would remove the first tubular and a
small portion of the cement between the first tubular and the
second tubular. When the first upward cut is complete, the spindle
housing 5080 would be lowered back down along the Z-axis to the
start position of the first cut and the Y-axis hydraulic cylinder
5016 would move the cutting device 5015 further into the nested
tubulars now that the innermost first tubular has been removed. The
next cut would use milling inserts 5104 further up the cutting
device 5015 to cut the tubulars as the spindle housing 5080 is then
feed vertically up the Z-axis a height programmed while
simultaneously rotating in the W-axis to spiral mill cut the length
of the next tubular and cement.
[0330] This technique is repeated until the final cut. The
remaining life of the lower most inserts 5104 are reserved to make
the final cut through the tubular that is the farthest into the
formation, as the lower most milling inserts are used mostly for
cutting cement until the final cut. By continuing in this manner,
the tubular cutting is spread across the entire cutting device 5015
to maximize the cutting ability.
[0331] Additionally, this embodiment acts as a type of pump,
directing the fluid flow into the wellbore while ejecting any chips
or debris resulting from the cutting process down the wellbore.
This ejecting action is accomplished by orienting the troughs 5108
between the rows of inserts 5104 backwards (e.g. reverse cutter)
and rotating the rotary mill cutter 5015 clockwise. Traditional
cutters are oriented with a "forward" cutter.
[0332] Traditional systems have to feed pressurized lubricant from
the surface into the bearing assemblies or use sealed bearings. In
contrast, this embodiment has a lubricant hole 5110 in the shaft
5084 that traverses from the outside of the shaft 5084 to the
inside opening 5112 which allows lubricant to flow onto the shaft
5084 and coat the shaft 5084 to reduce friction as the rotary mill
cutter 5015 and shaft 5084 rotates. The rotary mill cutter 5015 and
the shaft 5084 contain pressurized lubricant in a reservoir. A
piston (not shown) is attached to an opening 5112 in the base of
the rotary mill cutter 5015 to pressurize the lubricant. When the
shaft 5084 is connected to the spindle hydraulic motor 5082 a seal
is created below the lubricant hole 5110 such that the lubricant
does not leak. When the cutting device 5015 needs to be serviced,
the lubricant can be changed by removing the piston. By filling the
rotary mill cutter 5015 with pressurized lubricant, additional
vibration reduction can be achieved.
[0333] Unlike traditional cutters this embodiment has no connection
point between the shaft 5084 and the cutting device 5015 (e.g. it
is made from a single piece of metal). This increases the strength
and decreases the complexity thereby making this embodiment more
reliable than traditional cutters.
[0334] In one embodiment the cutting device 5015 measures
approximately one foot in length and approximately four inches in
diameter, however other lengths and diameters could be employed
depending on the particular application. Also in this embodiment,
the insert face 5106 is angled about nine degrees off the
centerline, although other angles could also be employed depending
on the particular application.
[0335] FIGS. 41A and 41B depict the tool with the steady rest 5120.
The steady rest 5120 provides an offset point to reduce vibration,
provide stability for the cutting device 5015, and counteract the
force of the cutting device 5015 pushing against the tubulars
and/or formation. As such, the steady rest is positioned such that
it impacts the wellbore on the opposite side from the arcing motion
of the spindle swing arm 5014. Additionally, the steady rest 5120
provides a safety mechanism in case one or more tubulars shifts
during cutting.
[0336] It is not uncommon for tubulars to shift during cutting for
example if the tubular was not cemented well. These shifts could
pin the tool in the wellbore and make retrieval difficult or
impossible. In one embodiment, the steady rest 5120 is coupled to
the tool with shear bolts 5121 and 5122 and extends below the
cutting device 5015. In one embodiment there are two levels of
shear bolts. If the first level of shear bolts 5121 gives way, the
steady rest 5120 will shift inward (e.g. the steady rest pivots out
of the way of the shifting tubular. This would represent a minor
shift in the tubular. If this occurs, the tool and the steady rest
are still retrievable. If the second level of shear bolts 5122
gives way, which represents a significantly more violent shift, the
steady rest will separate from the spindle housing 5080 and the
steady rest 5120 will remain in the wellbore; however, the robotic
rotary mill (downhole assembly) would still be retrievable.
[0337] The steady rest bearing 5123 provides the third major
contact point between the tool and the wellbore. The first being
the exposed portion of the spindle swing arm 5014 while cutting the
first innermost tubular, the second being the milling spindle
housing 5080 rubbing on the first innermost tubular as the mill
cutter 5015 is cutting the first innermost tubular, and the third
being the steady rest bearing 5123. These three major points of
contact provide a very stable cutting platform and significantly
reduce unwanted vibration.
[0338] In one embodiment, the steady rest 5120 is about 42'' long.
This permits the steady rest to engage against the inner wall of
the innermost tubular for the majority, if not all, of the cut. In
other embodiments, the steady rest 5120 may be more or less than
42'' long. In order to make cuts with a vertical distance (e.g.
along the Z-axis) in excess of 54'' (e.g. 42'' travel with the
steady rest engaged+12'' for the length of one embodiment of the
cutting device 5015 itself): (i) a longer steady rest 5120 could be
employed, (ii) the top most 54'' of the cut may be completed, then
the tool repositioned about 54'' below the bottom of the first cut
to begin a new series of cuts; (iii) the steady rest 5120 could be
engaged against the innermost tubular wall only for a portion of
the cut (e.g. the first cut, because it is generally the longest
cut, could have some portion of its cut made without the steady
rest 5120 engaged); and/or (iv) a longer rotary mill cutter 5015
could be used. It is preferable for the largest diameter cuts that
the steady rest be engaged against the innermost wall.
[0339] In one embodiment, the steady rest is not used if the
cutting device 5015 vibrations are small. The Clymer Technologies
model Terrella6 v2 (not shown) provides vibration graphical
displays to the operators monitor (not shown).
[0340] The disclosed subject matter covers the scope of
functionality in a holistic way. Although described with reference
to particular embodiments, those skilled in the art, with this
disclosure, will be able to apply the teachings in principles in
other ways. All such additional embodiments are considered part of
this disclosure and any claims to be filed in the future.
* * * * *