U.S. patent number 3,638,732 [Application Number 05/002,241] was granted by the patent office on 1972-02-01 for underwater wellhead electric connection apparatus for submerged electric motor driven well pumps and method of installation.
This patent grant is currently assigned to Vetco Offshore Industries, Inc.. Invention is credited to James W. E. Hanes, Fritz R. Huntsinger.
United States Patent |
3,638,732 |
Huntsinger , et al. |
February 1, 1972 |
**Please see images for:
( Certificate of Correction ) ** |
UNDERWATER WELLHEAD ELECTRIC CONNECTION APPARATUS FOR SUBMERGED
ELECTRIC MOTOR DRIVEN WELL PUMPS AND METHOD OF INSTALLATION
Abstract
An underwater bottom hole electrically driven well pump has an
electric power cable extending to the wellhead, a connectable and
disconnectable electrical connection being provided at the wellhead
between the cable and the power cable adapted to extend to a power
source, the connection being disconnectable and connectable at the
wellhead to permit the pump to be pulled from the well, or run back
into the well, through the wellhead and production tree without
necessitating removal of the wellhead and production tree.
Inventors: |
Huntsinger; Fritz R. (Ventura,
CA), Hanes; James W. E. (Ventura, CA) |
Assignee: |
Vetco Offshore Industries, Inc.
(Ventura, CA)
|
Family
ID: |
21699864 |
Appl.
No.: |
05/002,241 |
Filed: |
January 12, 1970 |
Current U.S.
Class: |
166/379; 166/68;
166/65.1; 166/368 |
Current CPC
Class: |
E21B
17/023 (20130101); E21B 33/035 (20130101); E21B
17/028 (20130101); E21B 43/128 (20130101); E21B
33/0407 (20130101) |
Current International
Class: |
E21B
33/035 (20060101); E21B 33/04 (20060101); E21B
33/03 (20060101); E21B 17/02 (20060101); E21b
033/035 (); E21b 043/01 (); E21b 023/04 () |
Field of
Search: |
;166/.5,.6,65,67-68.5,75,77.5,85,89,315 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Novosad; Stephen J.
Claims
We claim:
1. In apparatus for conducting electric current to an electrically
operated subsurface device disposed in a well bore: hanger means at
the top of the well bore; a landing head removably supported in
said hanger means; first electric conductor means in said landing
head having a first terminal; a support shiftable into and from
operative relation to said landing head; second electric conductor
means carried by said support and having a second terminal adapted
to be brought into and from contact with said first terminal in
response to movement of said support relative to said landing head;
coengaging orienting means on said landing head and hanger means
placing said first electric conductor means in a position aligned
with said second electric conductor means; said shiftable support
and second conductor means being movable from obstructing relation
to said landing head to permit withdrawal of said landing head from
said hanger means.
2. In apparatus as defined in claim 1; said support being mounted
in said hanger means and shiftable therein in one direction to
contact said second terminal with said first terminal and in the
opposite direction to disconnect said second terminal from said
first terminal to remove said support and second conductor means
from said obstructing relation to said landing head.
3. In apparatus as defined in claim 1; said support being shiftable
into said landing head to contact said second terminal with said
first terminal and out of said landing head to disconnect said
second terminal from aid first terminal and to remove said support
and second conductor means from said obstructing relation to said
landing head.
4. In apparatus as defined in claim 1; said landing head being
movable longitudinally of said hanger means into and out of said
hanger means; said support being shiftable longitudinally into said
landing head to contact said second terminal with aid first
terminal and longitudinally out of said landing head to disconnect
said second terminal from said first terminal and to remove said
support and second conductor means from said obstructing relation
to said landing head.
5. In apparatus as defined in claim 1; said support being shiftable
longitudinally of aid landing head in one direction to contact said
second terminal with said first terminal and in the opposite
direction to disconnect said second terminal from said first
terminal and to remove said support and second conductor means from
said obstructing relation to said landing head.
6. In apparatus as defined in claim 1; and means for preventing
fluid from passing to said first and second terminals when said
terminals are in full contact with each other.
7. In apparatus as defined in claim 1; and means for placing said
landing head in a predetermined position within said hanger means
to insure alignment between said terminals.
8. In apparatus for conducting electric current to an electrically
operated subsurface device disposed in a well bore: hanger means at
the top of the well bore; a landing head removably supported in
said hanger means; first electric conductor means in said landing
head having a first terminal; a support shiftable into and from
operative relation to said landing head; second electric conductor
means carried by said support and having a second terminal adapted
to be brought into and from contact with said first terminal in
response to movement of said support relative to said landing head;
said shiftable support and second conductor means being movable
from obstructing relation to aid landing head to permit withdrawal
of said landing head from said hanger means; said hanger means
having a longitudinal passage in which said landing head is
supported; said support being mounted in said hanger means and
shiftable therein in one direction laterally of said passage and
into said passage to contact said second terminal with said first
terminal and in the opposite direction to disconnect said second
terminal from said first terminal and to remove said support and
second conductor means completely from said passage.
9. In apparatus for conducting electric current to an electrically
operated subsurface device disposed in a well bore: hanger means at
the top of the well bore; a landing head removably supported in
said hanger means; first electric conductor means in said landing
head having a first terminal; a support shiftable into and from
operative relation to said landing head; second electric conductor
means carried by said support and having a second terminal adapted
to be brought into and from contact with said first terminal in
response to movement of said support relative to said landing head;
said shiftable support and second conductor means being movable
from obstructing relation to said landing head to permit withdrawal
of said landing head from said hanger means; and coengaging means
on said landing head and hanger means for turning said landing head
to a predetermined angular position in said hanger means to insure
alignment between said terminals.
10. In apparatus as defined in claim 9; said hanger means having a
longitudinal passage in which aid landing head is supported; said
support being mounted in said hanger means and shiftable therein in
one direction laterally of said passage and into said passage to
contact said second terminal with said first terminal and in the
opposite direction to disconnect said second terminal from aid
first terminal and to remove said support and second conductor
means completely from said passage.
11. In apparatus for conducting electric current to an electrically
operated subsurface device disposed in a well bore: hanger means at
the top of the well bore; a landing head removably supported in
said hanger means; a first cable carried by and depending from said
landing head, said cable having one or more first electric
conductors, each conductor having a first terminal, dielectric
material in said head insulating said one or more conductors from
said head; a support shiftable into and from operative relation to
said landing head; a second cable extending from said support, said
second cable having one or more second electric conductors, each
second conductor having a second terminal, dielectric material in
said support insulating said one or more second conductors from
said support; shifting of said support toward said landing head
contacting said one or more second terminals with said one or more
first terminals; said support and second electric conductors being
movable from obstructing relation to said landing head to permit
withdrawal of said landing head from said hanger means.
12. In apparatus as defined in claim 11; and coengaging means on
said landing head and hanger means for turning said landing head to
a predetermined angular position in said hanger means to insure
alignment between said one or more first terminals and said one or
more second terminals.
13. In apparatus as defined in claim 11; said hanger means having a
longitudinal passage in which said landing head is supported; said
landing head having a cavity therein into which said support is
movable to contact said one or more second terminals with said one
or more first terminals, said support being withdrawable from said
cavity to remove said one or more second terminals from contact
with said one or more first terminals and from said cavity to
permit withdrawal of said landing head from said hanger means.
14. In apparatus as defined in claim 11; said hanger means having a
longitudinal passage in which said landing head is supported; said
landing head having a cavity therein, said cavity axis extending
laterally of the axis of said passage; said support being shiftable
on said hanger means laterally of said passage and into and from
said passage and cavity to selectively contact said one or more
second terminals with said one or more first terminals or to remove
said one or more second terminals from contact with said one or
more first terminals and said support from said passage to permit
withdrawal of said landing head from said hanger means.
15. In apparatus as defined in claim 11; said hanger means having a
longitudinal passage in which said landing head is supported; said
landing head having a cavity therein, said cavity axis extending
laterally of the axis of said passage; said support being shiftable
and said hanger means laterally of said passage and into and from
said passage and cavity to selectively contact said one or more
second terminals with said one or more first terminals or to remove
said one or more second terminals from contact with said one or
more first terminals and said support from said passage to permit
withdrawal of said landing head from said hanger means; and means
for shifting said support on said hanger means into and from said
passage and cavity.
16. In apparatus as defined in claim 11; said hanger means having a
longitudinal passage in which said landing head is supported; said
landing head having a cavity therein, said cavity axis extending
laterally of the axis of said passage; said support being shiftable
on said hanger means laterally of said passage and into and from
said passage and cavity to selectively contact said one or more
second terminals with said one or more first terminals or to remove
said one or more second terminals from contact with said one or
more first terminals and said support from said passage to permit
withdrawal of said landing head from said hanger means; and means
for shifting said support on said hanger means into and from said
passage and cavity; said shifting means comprising a nut coupled to
said support and threaded on said hanger means, whereby rotation of
said nut feeds said support laterally of said passage.
17. In apparatus adapted for use in a well bore having a tubular
string therein: an electrically operated subsurface device adapted
to be set in the tubular string; hanger means at the top of the
well bore; a landing head removably supported in said hanger means;
a first electric conductor means extending from said device to said
landing head and having a first terminal in said landing head; a
support shiftable into and from operative relation to said landing
head; second electric conductor means carried by said support and
having a second terminal adapted to be brought into and from
contact with said first terminal in response to movement of said
support relative to said landing head; said shiftable support and
second conductor means being movable from obstructing relation to
said landing head to permit withdrawal of said landing head, first
conductor means and subsurface device from the well bore and hanger
means.
18. In apparatus as defined in claim 17; said support being mounted
in said hanger means and shiftable therein in one direction to
contact said second terminal with said first terminal and in the
opposite direction to disconnect said second terminal from said
first terminal and to remove said support and second conductor
means from said obstructing relation to said landing head.
19. In apparatus as defined in claim 17; said hanger means having a
longitudinal passage in which said landing head is supported; said
support being mounted in said hanger means and shiftable therein in
one direction laterally of said passage and into said passage to
contact said second terminal with said first terminal and in the
opposite direction to disconnect said second terminal from said
first terminal and to remove said support and second conductor
means completely from said passage.
20. In apparatus as defined in claim 17; said landing head being
movable longitudinally of said hanger means into and out of said
hanger means; said support being shiftable longitudinally into said
landing head to contact said second terminal with said first
terminal and longitudinally out of said landing head to disconnect
said second terminal from said first terminal and to remove said
support and second conductor means from said obstructing relation
to said landing head.
21. In apparatus as defined in claim 17; said hanger means having a
longitudinal passage in which said landing head is supported; said
support being mounted in said hanger means and shiftable therein in
one direction laterally of said passage and into said passage to
contact said second terminal with said first terminal and in the
opposite direction to disconnect said second terminal from said
first terminal and to remove said support and second conductor
means completely from said passage; and coengaging means on said
landing head and hanger means for turning said landing head to a
predetermined angular position in said hanger means to insure
alignment between said terminals.
22. In apparatus as defined in claim 17; and means providing a
releasable connection between said first conductor means and
subsurface device to separate said first conductor means from said
device in response to a predetermined tensile pull taken on said
first conductor means.
23. In apparatus as defined in claim 17; wherein said subsurface
device is an electrically driven pump.
24. In apparatus adapted for use in a well bore having a casing
string therein: hanger means at the top of the well bore; a landing
head removably supported in said hanger means; a tubing string
secured to and depending from said landing head and disposed within
the casing string; an electrically operated subsurface device in
said tubing string; first electric conductor means connected to
said subsurface device and extending upwardly therefrom and
externally of the tubing string to said landing head, said
conductor means having a first terminal in said landing head; a
support; second electric conductor means carried by said support
and having a second terminal adapted to be brought into and from
contact with said first terminal in response to longitudinal
movement of said support relative to said landing head; said
support and second conductor means being movable from obstructing
relation to said landing head to permit withdrawal of said landing
head, tubing string, subsurface device and first conductor means
from the well bore and hanger means.
25. In apparatus as defined in claim 24; wherein said subsurface
device is a pump.
26. The method of installing or removing electric conducting means
at a well bore location for use with an electrically operated
subsurface device disposed in the well bore, a hanger being located
at the top of the well bore, comprising securing the lower end of a
first electric cable to the subsurface device and its upper end to
a landing head, said cable having a first terminal, lowering the
landing head, electric cable and subsurface device until the
subsurface device with the cable attached thereto is located in a
desired position in the well bore and with the landing head seating
on the hanger; engaging orienting means on said landing head with
companion orienting means on said hanger to insure predetermined
angular positioning of said landing head and said first terminal in
said hanger; and moving a support carrying a second cable having a
second terminal into said landing head to contact said second
terminal with said first terminal.
27. The method of installing or removing electric conducting means
at a well bore location for use with an electrically operated
subsurface device disposed in the well bore, a hanger being located
at the top of the well bore, comprising securing the lower end of a
first electric cable to the subsurface device and its upper end to
a landing head, said cable having a first terminal, lowering the
landing head, electric cable and subsurface device until the
subsurface device with the cable attached thereto is located in a
desired position in the well bore and with the landing head seating
on the hanger; and moving a support carrying a second cable having
a second terminal into said landing head to contact said second
terminal with said first terminal; the landing head seating in an
axial bore in the hanger, the support being movable into the
landing head to a position preventing elevation of said landing
head from the hanger bore, and withdrawing the support and second
cable from the landing head to disconnect the second terminal from
the first terminal and permit upward elevation of said landing
head, first cable and subsurface device from the well bore and
hanger.
28. The method of installing or removing electric conducting means
at a well bore location for use with an electrically operated
subsurface device disposed in the well bore, a hanger being located
at the top of the well bore, comprising securing the lower end of a
first electric cable to the subsurface device and its upper end to
a landing head, said cable having a first terminal, lowering the
landing head, said cable having a first terminal, lowering the
landing head, electric cable and subsurface device until the
subsurface device with the cable attached thereto is located in a
desired position in the well bore and with the landing head seating
on the hanger; and moving a support carrying a second cable having
a second terminal into said landing head to contact said second
terminal with said first terminal; the landing head seating in an
axial bore in the hanger, the support being moved laterally into
the axial bore and landing head to a position preventing elevation
of said landing head from the hanger bore, and withdrawing the
support laterally from the landing head and completely from the
hanger bore to disconnect the second terminal from the first
terminal and permit upward elevation of said landing head, first
cable and subsurface device from the well bore and hanger.
29. The method of installing or removing electric conducting means
at a well bore location for use with an electrically operated
subsurface device disposed in the well bore, a hanger being located
at the top of the well bore, comprising securing the lower end of a
first electric cable to the subsurface device and its upper end to
a landing head, said cable having a first terminal, lowering the
landing head, electric cable and subsurface device until the
subsurface device with the cable attached thereto is located in a
desired position in the well bore and with the landing head seating
on the hanger; and moving a support carrying a second cable having
a second terminal into said landing head to contact said second
terminal with said first terminal; the landing head seating in an
axial bore in the hanger, the support being moved longitudinally
into the landing head to a position preventing elevation of said
landing head from the hanger bore, and withdrawing the support and
second cable longitudinally from the landing head to disconnect the
second terminal from the first terminal and permit upward elevation
of said landing head, first cable and subsurface device from the
well bore and hanger.
Description
The present invention relates to well production apparatus and
methods for installing and removing the same, and more particularly
to bottom hole electrically driven pumps used in underwater well
completions.
Submerged electrically driven pumps have been used on land wells
for many years. The electric cable extending downwardly in the well
bore to the electric motor passes through the wellhead by means of
a pressuretight fitting, running to a suitable electric power
source. When retrieval of the pump from such well is necessary, the
power line is disconnected from the power source, the wellhead is
removed, and the pump and power cable removed from the well. The
foregoing arrangement has been used with casing pumps installed in
the well bore, in which the pump is run on a wire line, or a string
of sucker rods, into the well casing and landed on a casing seat at
the desired location of the pump, where it is packed off, the well
production being pumped up through the casing. In another
arrangement, a tubing string is run into the cased well and the
pump is run on a wire line or string of sucker rods into the tubing
string and landed on a seat therein, at which point the pump is
packed off and the production pumped upwardly through the tubing
string to the top of the well bore.
It is comparatively difficult and costly to remove and reinstall a
wellhead or production tree at the top of a well bore which is to
be pumped with an electrically powered submerged pump, particularly
where the wellhead and production tree are installed at the mudline
or floor of a subsea or other underwater location. As an example,
withdrawal of the pump becomes necessary if it sands up, or if the
production tree is to be removed for any reason.
By virtue of the present invention, a casing or tubing submersible
pump can be removed without the necessity for removing the wellhead
or production tree, and the electric motor-operated pump can also
be run to its landing position in the casing or tubing without
materially disturbing the wellhead or production tree. Accordingly,
the remedial cost of pump replacement is reduced to a minimum.
The invention further involves the provision of an electrical
connection at the wellhead or production tree between the electric
cable extending downwardly from the production tree or wellhead to
the electric motor driven pump and a power cable extending from the
wellhead or production tree to a suitable remotely located power
switch, the electric connection being readily connectable and
disconnectable without removal of the production tree or wellhead,
to permit the pump and cable connected thereto to be removed
through the wellhead. If tubing is in the well casing and it sands
up, the tubing can also be removed without removal or other
disturbance of the production tree or wellhead.
In connection with an underwater well bore and wellhead, the
electrical connection at or adjacent to the wellhead can be readily
disconnected or connected to permit withdrawal of the pump or
tubing string, if one is present, from the well bore, and the
rerunning of such equipment in the well bore, all without affecting
the wellhead or production tree.
This invention possesses many other advantages and has other
purposes which may be made more clearly apparent from a
consideration of several forms and methods embodying the invention.
These forms and methods are shown and described in the present
specification and in the drawings accompanying and constituting a
part thereof. They will now be described in detail, for the purpose
of illustrating the general principles of the invention; but it is
to be understood that such detailed description is not to be taken
in a limiting sense.
Referring to the drawings:
FIGS. 1a and 1b together constitute a combined longitudinal section
and side elevational view of one embodiment of the invention, FIG.
1b being a lower continuation of FIG. 1a;
FIG. 2 is an enlarged longitudinal section through the electrical
connector portion of the apparatus illustrated in FIG. 1a, with the
electrical connection completed;
FIG. 3 is a view similar to FIG. 2, disclosing parts of the
electrical connector in disengaged position;
FIG. 4 is a longitudinal section, on an enlarged scale, of a
releasable connection between the cable and pump forming part of
the apparatus illustrated in FIG. 1b;
FIGS. 5a and 5b together constitute a combined longitudinal section
and side elevational view of another embodiment of the apparatus,
FIG. 5b being a lower continuation of FIG. 5a;
FIG. 6 is a combined longitudinal section and side elevational view
of yet another form of the invention;
FIG. 7 is an enlarged combined longitudinal section and side
elevational view through the electrical connector portion of the
apparatus illustrated in FIG. 6;
FIG. 8 is a cross section taken along the line 8--8 on FIG. 7.
The form of invention illustrated in FIGS. 1 to 4 involves a casing
type of electric motor-driven pump 10 of any known, usual design,
which is disposed in a casing string 11 located in a well bore A
and passing through a plurality of producing zones 12, the
production passing into the lower portion of the casing string
through a plurality of perforations 13, and then through inlet
perforations 14 into the submerged pump 10, which is landed on a
casing pump seat 15 in sealed relation thereto. The well bore A
underlies a body of water and extends downwardly from the mudline
of floor M underlying the water. A typical wellhead combination W
is disclosed in connection with the casing string. Thus, the bowl
16 of a guide structure rests upon the floor M, having ports 17 at
its lower end. A hanger 18 for a string of conductor casing 19 is
supported on a shoulder 20 of the guide structure, the conductor
pipe extending downwardly from the mudline M to a desired depth.
Another casing hanger 21 seats upon a shoulder 22 in the conductor
hanger 18, a protection casing string 23 being secured thereto, and
depending downwardly in the well bore to a required depth, which is
usually substantially below the depth to which the conductor casing
19 extends. The production casing string 11, in which the pump 10
is disposed, is secured to a casing hanger 24 resting upon a
shoulder 25 in the hanger housing 21 secured to the protection
casing string 23.
The manner of running the various strings of casing and the
completion of the casing system is known. In general, the entire
guide structure is supported on the drilling vessel (not shown),
together with the bowl 16, which is an integral part of the guide
structure. The conductor hanger 18 is held in the guide structure
16 by means of a lock ring 26, and the desired length of conductor
19 is secured to the conductor hanger. This combination is now
lowered by means of a left-hand running tool (not shown) on drill
pipe (not shown), the running tool threadedly engaging the
left-hand threads 27 of the conductor hanger, and also being
provided with a stinger (not shown) with a jetting head (not shown)
at its lower end that is disposed inside the conductor pipe 19 and
terminates a short distance from the bottom of the latter. A
suitable fluid is pumped down the stinger for discharge from the
jetting head, when the whole combination has been lowered to the
point in which the lower end of the conductor is at the mudline M,
to jet the desired length of hole in the formation, which will be
determined by the engagement or landing of the guide structure 16
on the mudline. The annulus surrounding the conductor pipe 19 is
now cemented in place in a known manner, with the cement returns
coming up the annulus and spilling over at the mudline through the
ports 17 in the bowl. The running string is now retrieved by
unscrewing the running tool at the left-hand threads 27 of the
conductor hanger.
If jetting of the hoe is not feasible, then a drill bit and hole
opener combination (not shown) is run through the conductor 19 and
a hole made for the latter. While the drill string with the drill
bit and expanding hole opener are still in communication with the
hole, the conductor pipe 19 and the guide base and its bowl 16 are
stripped into the hole by lowering it on guide lines (shown in FIG.
6). The drilling string is then removed and the conductor 19
cemented in place by a known displacement method.
The drilling of the well bore A is continued by means of suitable
drilling bits and a drilling string to a desired depth to receive
the protection string of casing 23. This protection string is
secured to the hanger housing 21 by means of a suitable left-hand
threaded running tool which threadedly engages the left-hand
threads 28 of the hanger housing 21. This combination is lowered
from the drilling vessel until the hanger housing 21 lands in the
conductor hanger, resting upon the shoulder 25 of the latter, the
hanger housing carrying a split expandable lock ring 29 therein
which contracts past the lock ring 26, secured to the bowl 16, and
then snaps into an internal groove 30 formed between the lock ring
26 and the hanger housing 18 to prevent upward movement of the
inner hanger housing 21. The protective casing string 23 is then
cemented in place, with the returns passing through a passage 31 in
the hanger housing and dumping into the ocean near its floor. The
running tool is then retrieved by unscrewing it at the left-hand
thread 28 of the hanger housing 21.
A blowout preventer stack (not shown) is secured to the lower
portion of a marine riser (not shown) and is run in place from the
drilling vessel and connected to the wellhead by means of a
connector similar to a connector 32 shown in the drawings, the
connector resting upon the top of the hanger housing 21 and
carrying an inherently contractable lock ring 33 in its groove 34
which will snap into a peripheral groove 35 in the upper portion of
the hanger housing.
A hole A is now drilled to the desired depth and through the
producing zones 12, and of a diameter to receive the production
casing string 11 in which the pump 10 is to be installed. By means
of a suitable running tool connected to the casing hanger 24
secured to the production casing string 11, the latter is lowered
from the drilling vessel through the marine riser and blowout
preventing stack into the well bore A to the extent at which the
casing hanger 24 lands on a shoulder 37 in the hanger housing. The
casing string 11 is now cemented in place, beginning at the top of
the producing zones 12, the cement 40 discharging through a
suitable cement collar 38 and then passing upwardly through the
annulus 39 surrounding the production casing string to a location
above the mudline, the cement dumping out through the opening 41
provided by the removal of a plug 42 for the opening by a diver
prior to the commencement of the casing cementing operation.
The blowout preventer stack, marine riser, and connector are now
removed, and a production tree 43, with a connector 32 attached to
its lower end, then lowered from the drilling vessel and attached
to the wellhead hanger housing 21. A tubular extension 44 is
threadedly secured to the lower end of the production tree, its
lower end terminating just above the upper end of the production
casing string 11 so as to provide continuity of the passage for the
pump 10 through the apparatus when it is being elevated from the
casing, and when it is lowered thereinto to its position at which
it lands on the pump seat 15 in the lower portion of the production
casing string. The production tree 43 has a lateral flow line 45
communicating with the central passage through the tree, which is
secured to the tree in any suitable manner, as by means of a clamp
connection 46. The flow line has a suitable valve 47 therein for
shutting off or permitting flow of fluid therethrough.
The upper portion of the production tree 43 is provided with a
shutoff valve 48 and a quick connection 49, which allows for
connecting a small production riser 50 between the production tree
and a workover vessel (not shown) floating in the top of the
water.
As disclosed in the drawings, the pump 10 is connected, preferably
by means of a releasable connection 51, to a cable 52 which
combines a steel supporting cable with electrical conductors
therein, the upper ends of which are secured to a landing head 53
adapted to land on an upwardly facing internal shoulder 54 in the
production tree or head (FIGS. 2,3). The upper steel cable portion
is secured to a depending skirt or leg portions 55 of the pump
landing head by means of screws 56 secured to a socket 57 into
which the upper portion of the cable extends and is suitably
secured, the conductor portion or portions 58 of the cable itself
extending upwardly into an axial passage 59 in the landing head,
each of the conductors being received within one portion of a
conductive sleeve 60 that has a branch 61 forming a female socket
62 of an electrical connector C, extending radially toward a radial
passage 63 in the pump landing head and terminating inwardly of the
passage 63 and periphery of such head 53. Dielectric material 64,
such as nylon, is cast in the head passage 59, being secured to the
head by integral circumferential ribs 65 of the dielectric
insulating material being received within internal grooves 66 in
the head. For the purpose of running-in and retrieving the pump, a
connector 67 is threadedly secured in the landing head above the
dielectric material, this connector having a fishing neck 68 and
head 69 at its upper portion adapted to coact with a suitable
running tool 70 (FIG. 5a) attached to the lower end of a wire line
71, by means of which the pump 10, cable 52 and landing head 53 are
run in and also retrieved.
The production head 43 has a lateral extension 73 which forms part
of a connectable and disconnectable electrical connector mechanism.
It is necessary to orient the lateral or radial extension 73 with
the pump landing head opening 63 and with respect to the socket 62
disposed therein, the socket and opening 63 being in a position for
appropriate alignment with the axis of the lateral arm 73 of the
production head when the pump landing head 53 lands upon its
companion shoulder 54. The parts are properly oriented, as a result
of lowering the pump landing head in the production head, by
providing a longitudinal key 74 on the landing head diametrically
opposite the lateral landing head passage 63, the lower end of the
key engaging an upwardly directed surface of a helical cam 75
extending around the production head 43, so that upon axial sliding
of the key along the cam, the pump landing head 53 is turned to an
extent at which its landing on its companion shoulder 54 positions
the lateral passage 63 and the socket 62 in coaxial relation with
the lateral arm 73 of the production head.
Axially slidably mounted within the arm 73 is a connector sleeve 76
which is prevented from rotating with respect to the arm 73 by a
radial pin 77 secured to the arm and slidable in a longitudinal
groove or keyway 78 in the sleeve 76. This sleeve has a male
conductive plug 79 which is affixed to the conductive terminal of a
conductor 80 forming part of a power cable 81 extending to a
suitable power source above water or on an adjacent shore. The male
plug 79 and conductor 80 disposed within the connector sleeve 76
are held therein and insulated therefrom by molding a suitable
dielectric material 82 in the sleeve and around the conductive
members, the insulating material being secured in place by integral
circumferential ribs 83 thereon received in companion internal
grooves 84 in the connector sleeve 76. Extending axially from the
female socket 62 is a flaring mouth 85 of the insulating material
64 adapted to coact with a companion tapered portion 86 at the
inner end of the insulating material 82. The insulating material 64
has another tapered or outwardly flaring surface 87 adapted to
coact with the companion tapered surface 88 on the insulating
portion 82, to provide assurance that the engagement of the tapered
surfaces with one another will provide a leakproof seal
therebetween (see FIG. 2).
The connector sleeve 76 is shifted axially of the arm 73 to bring
the male plug 79 into a position fully received within the female
socket and making good electrical contact therewith. Initially, the
sleeve 76 is in its outer position so as not to obstruct the
passage 90 in the production head 43, there being one or a
plurality of seal rings 91 in the arm slidably and sealingly
engaging the periphery of the connector sleeve 76 to prevent
passage of fluid therebetween. The landing head 53 carries a
suitable seal ring 92 in a position surrounding its radial passage
63 which is adapted to be engaged by the periphery of the connector
sleeve 76 when the latter is moved inwardly thereinto, to prevent
leakage of fluid therebetween. Initially, the cavity 63 in the
landing head 53 with which the socket 62 is aligned is filled with
a silicon jell 93 which has high dielectric characteristics. The
movement of the connector sleeve 76 and its interior parts toward
and into the cavity will cause the fluid in advance thereof to pass
through the clearance space between the landing head 53 and the
production head 43, until the connector sleeve 76 engages the head
seal ring 92, whereupon the silicon jell is forced out of the
cavity 63 through a passage 94 in the pump landing head, the
silicon jell moving through a suitable check valve 95 into the
production head 43 above the landing head. The check valve, which
may be of the spring loaded ball type, permits outward flow of
fluid substances from the cavity 63 and passage 94 to the exterior
of the landing head 53, but prevents return flow of fluid
thereinto. Inward feeding of the connector sleeve 76 continues
until the tapered surfaces 85, 86 and 87, 88 (FIG. 2) coengage.
After the landing head 53 is disposed in its appropriate position
within the production head 43, and with its radial cavity 63
aligned with the lateral arm 73, the connector sleeve 76 is moved
inwardly. As specifically illustrated in the drawings, its
longitudinal shifting is effected by means of a nut 100 having a
threaded connection with the arm 73. This nut has an inwardly
directed flange 101 received within a peripheral groove 102 in an
outer portion of the connector sleeve, the nut being rotatable by a
diver grasping a radial rod 103 suitably affixed to the nut.
Rotation of the nut 100 in one direction will feed it outwardly
along the arm 73 to the extent limited by engagement of a set screw
104 threaded in the inner portion of the nut with a stop shoulder
105 on the arm. When such engagement occurs, assurance is had that
the connector sleeve 76 and the insulation 82 therein, as well as
the male plug conductor 79, have been removed completely from the
passage 90 extending through the production head 43. In the event
that the production tree is to be removed from the hanger housing
21, the set screw 104 can be completely unthreaded from the nut and
the latter threaded completely off the tubular arm 73, permitting
the connector sleeve 76 and parts therewithin to be removed
completely from the arm.
Rotation of the rod 103 and nut 100 in the opposite direction from
that just described will feed the connector sleeve 76 inwardly for
the purpose of making the electrical connection between the female
socket 62 and the male plug 79, as described above.
In running the submersible pump 10 into the well bore, the
connector sleeve 76 and each male plug 79 are disposed within the
production head arm 73 in their outer position completely clear of
the production head passage 90. The electric motor pump 10 is
connected to the cable 52, the upper end of which is secured to the
pump landing head 53 by means of a support member 57 and the screws
56. The cavity 63 is filled with the silicon jell 93 and the
running tool 70 attached to the fishing head 69 secured to the
landing head 53, the combination of apparatus then being lowered
from the drilling vessel through the production riser 50,
production head 43 and into the casing 11, until the submersible
pump 10 lands on and seals against the pump seat 15, the key 74
contacting the cam surface 75 in the production tree and orienting
the landing head 53 so that its cavity 63 and socket or terminal 62
are appropriately locating with respect to the production head arm
73 when the head 53 lands upon its companion shoulder 54. The rod
103 and nut 100 are then rotated to feed the connector sleeve 76
axially inwardly of the arm, the silicon jell 93 being displaced
outwardly through the passage 94 and spring-loaded check valve 95
until the connector sleeve is disposed to its maximum inward
extent, at which time the tapered surfaces 85, 86 and 87, 88
coengage and the socket 63 fits snugly in good electrical contact
around the male plug 79.
The running tool 70 is now released from the head 69 and the marine
production riser 50 removed, the valve 48 being closed and the
valve 47 in the flow line 45 opened. Oil from the several oil
producing zones 12 migrates down the annulus B around the
production casing string 11, passing through the casing
perforations 13 into the casing below the pump 10. The production
is sucked up by the pump through the perforated tail pipe 110 and
is pumped up through the casing 11, discharging through the flow
line 45 to the storage tanks (not shown), or the like.
In the event it is desired to pull the pump 10 from the casing, the
flow line valve 47 is closed and the shutoff valve 48 opened. The
nut 100 is rotated in a direction to feed the connector sleeve 76
outwardly and break the electrical connection between the male plug
79 and the female socket 62, the sleeve being moved outwardly to
its fullest extent so that the sleeve, male plug and dielectric
material 82 are completely removed from the production head passage
90 (FIG. 3). Thereafter, a retrieving tool 70 (FIG. 5a) is lowered
on a wire line 71 from a floating vessel, the retrieving tool being
connected to the fishing head 69, in a known manner. An upward pull
is now taken on the wire line and retrieving head to pull the pump
landing head 53, cable 52 and pump 10 upwardly, the upward movement
continuing until the pump has been completely removed and elevated
to the floating vessel. Such action takes place without disturbing
the casing heads and casing strings attached thereto. If desired,
the production tree 43 can be completely disconnected from the
hanger housing 21 by releasing the manual connector 32 therefrom,
in a known manner.
In the event that a sand body has built up on top of the pump 10,
which prevents its release and removal from the production casing
string 11, a breakaway fitting or releasable connection 51 between
the lower portion of the cable 52 and the pump 10 is provided so
that the cable can be disconnected from the pump, thereby
permitting the cable 52 and landing head 53 to be retrieved.
Thereafter, a suitable fishing tool can be lowered into the casing
for the purpose of jarring the pump loose and effecting its
recovery from the casing.
A breakaway or releasable cable connection 51 to the pump is
illustrated in FIG. 4. As shown therein, the upper end of the
electric motor driven pump 10 has a male plug or terminal 121
fitting within a female socket or terminal 122 embedded in
dielectric material 123 cast within a conductor housing 124 having
an external flange 125 secured to the end portion of the motor case
or housing by a plurality of longitudinally extending cap screws
126 designed to pull apart or fail when subjected to a
predetermined tensile pull. The conductor housing 124 is filled
with dielectric material 127 through its upper end, which will
surround the electric conductor 128 connected to the female
terminal 122, the bleeding of air from the housing during the
filling operation being permitted by the provision of a vent port
129 in the lower portion of the conductor housing. The housing 124
is threadedly secured to a spelter socket 130 into which the cable
52 extends. The steel strands of the cable are separated and spread
apart in the spelter socket, after which the socket is filled
through a port 131 with a resin 132 which firmly anchors the steel
cable strands to the socket 130, and also the conductor housing 124
connected thereto.
In the event the taking of an upward pull on the wire line 71,
retrieving tool 70, pump landing head 53, and cable 52 does not
result in the retrieving of the submersible pump 10, the extent of
such pull can be increased until, at a predetermined force, the cap
screws 126 will pull apart, thereby effecting a breaking of the
connection between the conductor and the pump by virtue of the
pulling off of each female conductive sleeve 122 from its male plug
121. The equipment in the casing and production head can now be
elevated completely therefrom and withdrawn to the floating vessel,
after which, as stated above, a suitable fishing tool can be
lowered for recovery of the submersible pump.
In the form of invention illustrated in FIGS. 5a and 5b, the
electric motor-driven pump 10 is disposed in a tubing string 200
run into the casing string 11. The tubing string extends into the
casing string to a location within the production zone region 12 of
the casing, a packer 201 on the tubing string sealing off against
the inner wall of the well casing below the casing hanger 24, such
location being determined by a tubing hanger 202 engaging a
supporting shoulder 203 on the production tree housing 43, the
tubing hanger being held in place by a lock screw 204 threaded into
the Christmas or production tree housing and received within a
peripheral groove 205 therein. The tubing string has perforations
206 above the location of the packer 201, so that the oil delivered
by the pump into the tubing string 200 can flow outwardly through
the perforations and into the lateral branch 45 of the flow line
controlled by the valve 47. A seat protector 207 may be disposed in
the hanger housing to protect the lateral branch of the flow line,
but such seat protector is removed before the tubing string 200 is
run in the well bore by means of the Christmas tree housing, the
manual connector 32 securing the latter to the hanger housing 21 in
the same manner as in the other form of the invention.
The pump landing head 53, lateral electric connector 73, 76, 100,
etc., orienting key 74 and cam 75, running-in head 67-69, and the
like, are the same as in the other form (FIGS. 1 to 4) of the
invention, except that the landing shoulder 54 for the landing head
may provided by the upper end of the tubing hanger 202.
The pump 10 is run in on the cable 52 and pump landing head 53 in
the same manner as in the other form of the invention, until the
pump lands on its tubing seat 15. The electric connection and
disconnection at the landing head is made in the same manner as in
the other form of the invention. In the event that the tubing
becomes sanded up above the pump 10, precluding the latter from
operating, the electric connector is disconnected in the same
manner as in the other form of the invention, nd the retrieving
tool 70 lowered to engage the retrieving head 69 for withdrawal of
the pump. In the event that the sand in the casing prevents
recovery of the pump, then a pull can be taken on the cable 52 in a
sufficient amount to disrupt the breakaway fitting 51 in the same
manner as in the other form of the invention, whereupon the cable
52 and the pump landing head 53 can be retrieved. The lock screw
204 is then released and through use of suitable retrieving
mechanism coupled to the tubing hanger 202, the tubing 200 with the
pump 10 therein can be withdrawn from the well bore.
As in the other form of the invention, the casing hanger heads 18,
21, 24 and the Christmas tree housing 43 need not be disturbed
before the pump 10 can be retrieved. The pump or another pump can
be relowered in the well bore and placed in operative association
with the tubing seat 15, the electric connector C being reconnected
so that the pump can commence its pumping action to deliver the
well production through the flow line 45 to storage tanks, or the
like.
In the embodiment of the invention illustrated in FIGS. 6 to 8,
essentially the same assembly of casing hangers 18, 21, 24 and
concentric strings of casing 19, 23, 11 are disclosed as in the
other forms of the invention. A tubing string 200 is lowered into
the production casing string 11, the upper end of this string of
tubing being threadedly secured to a tubing hanger 302 adapted to
come to rest upon a suitable shoulder 303 in the casing hanger 24
and releasably held in position by a split latch ring 304 disposed
in a peripheral groove 305 in the tubing hanger receivable in an
internal circumferential groove 306 in the casing hanger. The
opposed sides of the groove 306 are tapered so that an upward pull
taken on the tubing hanger 302 will cam the latch ring 304 inwardly
and permit removal of the tubing hanger 302 and tubing 200 from the
casing hanger 24 and casing string 11.
The electric conductor cable 52 is also suspended from the tubing
hanger 302, the lower end of the electrical conductor making a
suitable electrical connection with the pump 10 disposed in the
production tubing 200. As shown, the upper end of the cable is
secured to a support member 310 having a flange 311 resting upon a
shoulder 312 in the tubing hanger 302 and being held downwardly
thereagainst by a retainer ring 313 attached to the tubing hanger
by longitudinally extending cap screws 314. The outer steel
stranded portion of the conductor cable is suitably mounted in the
support member 310, and each of its conductors 58 extends upwardly
through dielectric material 315 being attached to the cast into the
support member 310, the dielectric body 315 being attached to the
support member by integral ribs 316 thereon cast into internal
grooves 317 in the support member. The dielectric material extends
slightly above the upper end of the support member, each conductor
58 therein projects upwardly out of the dielectric material to form
a male plug or terminal 318. The electrical connector C also
includes an outer housing 319 adapted to telescope over the support
member 310 and to be sealed thereagainst by means of one or more
side seal rings 320 carried by the housing and sealingly engaging
the periphery of the support member. One or more companion electric
conductors 80 are disposed in the outer housing 319, being held
therein by dielectric material 321 cast within the housing passage
and secured thereto by dielectric ribs 322 received within
companion internal grooves 323 in the housing. Each conductor 80 in
the housing is secured to a female conductive sleeve 79 adapted to
receive the terminal plug 318. The dielectric member 321 projects
below the sleeve or sleeves 79, tapered surfaces 324 on the
dielectric bodies 315, 321 engaging when the connection has been
completed, to seal each connection 79, 318 against passage of
fluid.
The housing 319 is carried by the upper end member or portion 325
of the manual connection 32 which is adapted to telescope over the
hanger housing 21. Thus, the outer housing 319 has a shoulder 326
engaging the lower side of the end plate 325 of the manual
connector, a lock nut 327 being threaded on the reduced diameter
portion of the outer housing and bearing against the upper side of
such end plate. Leakage of fluid along the housing is prevented by
a suitable seal ring 328 on the end plate sealingly engaging the
periphery of the housing.
A production nipple 329 is received in the passage 330 of the
tubing hanger 302 in which the production tubing 200 is connected,
the upper portion of this nipple being sealed within the end plate
325. The oil delivered by the pump 10 through the tubing 200 will
pass through the nipple 329 and into a Christmas tree assembly 331
thereabove of any suitable combination of elements.
The female connector member 79, 80, 321 is attached to an
electrically conductive cable 340 extending to a fitting 341
carried by a bracket 342 suitably secured to the end plate 325. The
power cable (not shown) leading from the power source is suitably
attached to the cable 340 in the fitting 341 by means of a suitable
electrical connector (not shown) that can be threadedly secured to
the fitting, in a known manner.
The tubing hanger 302 is properly oriented with respect to the
hanger housing 21 by means of a spring-loaded orienting key 343
mounted in the tubing hanger 302 and adapted to be received in a
single orienting longitudinal keyway 344 cut across the threaded
portion 345 of the housing. By turning of the tubing hanger 302,
the key 343 snaps into the orienting keyway 344, which places the
production tubing 200 and the male connector 310 in an appropriate
relation for reception of the manual connector 32 and the fitting
329 and electrical connector member 319 carried thereby, when the
connector 32 is lowered along suitable guidelines extending to the
floating vessel and secured to lower guide posts 350.
The production tubing 200, pump 10 and electrical conductor 52 are
lowered from the floating vessel, the production tubing and
electrical conductor entering the production casing 11 and being
appropriately disposed to locate the lower portion of the tubing
and the pump carried thereby at the desired location in the well
casing, s determined by engagement of the tubing hanger 302 with
its seat 303, its lock ring 304 snapping into the companion locking
groove 306 in the casing hanger 24. The lowering tool, such as a
string of drill pipe (not shown) releasably secured to the tubing
hanger 302 is then turned until the key 343 snaps into the keyway
344, which insures the proper orienting of the tubing string 200
and of the male electrical connector members 58 relative to the
hanger housing 21, which has been located in a predetermined
position by means of its guide arms 360 and sleeves 361 slidable
along the posts 350 secured to the guide structure of the assembly
illustrated in the drawings. As set forth above, suitable
guidelines (not shown are connected to the guide posts 350, which
extend to the drilling vessel.
The Christmas tree assembly 331 with the manual connector 32 is
then lowered from the drilling vessel, the manual connector having
a guide frame 362 and sleeves 363 also slidable along the
guidelines, and then along the guide posts 350, the nipple 329
being appropriately aligned with the passage 330 in the tubing
hanger 302, and the outer housing 319 of the electrical connector C
being aligned with the male portions 318, 315, 310 of the
electrical connector, which are secured to the tubing hanger 302.
The connector 32 is lowered to its fullest extent over the hanger
housing 21, which will place the nipple 329 in sealed relation
within the hanger passage 330 and which will also telescope the
outer housing 319 over the lower cable support 310 and lace the
conductor sleeves 79 over the male plugs 318. The cavity 365
present within the outer housing 319 of the female connector is
filled with silicon jell prior to lowering of the connector and
Christmas tree toward the ocean floor M. Upon disposition of the
outer housing 319 over the lower support 310, such silicon jell is
forced out of the cavity through a spring-loaded check valve 366 to
the exterior of the outer housing, thus insuring that any sea
water, or the like, or other liquid in the outer housing 319 will
be dispelled from the outer housing cavity, and thus insuring the
presence of a good electrical connection between the male terminal
plugs 318 and the female terminal sleeves 79.
In the event that retrieval of the pump 10 is required, the
mechanical connector 32 is released from the hanger housing 21 and
elevated, together with the Christmas tree 331 thereabove, to the
drilling vessel, the bridging nipple 329 being removed from the
tubing hanger 302 and the female portions 319, 321, 80, 79 of the
electrical connector C being disconnected from the male portions
310, 315, 58 carried by the tubing hanger. Thereafter, a suitable
retrieving tool can be lowered on a suitable string of tubing and
connected to the tubing hanger 302, an upward pull being taken on
the retrieving string to cause retraction of the lock ring 306 from
the casing hanger groove 306 and withdrawal of the tubing hanger
302 from the casing hanger 24, as well as elevation of the tubing
string 200, pump 10 and electrical conductor 52 as a unit
completely from the casing 11 and to the floating vessel.
* * * * *