U.S. patent application number 14/512717 was filed with the patent office on 2018-03-15 for slip style rod spinner for pipe bursting machine.
The applicant listed for this patent is Earth Tool Company LLC. Invention is credited to Robert F. Crane, Walter George Thompson, Steven W. Wentworth.
Application Number | 20180073311 14/512717 |
Document ID | / |
Family ID | 54016866 |
Filed Date | 2018-03-15 |
United States Patent
Application |
20180073311 |
Kind Code |
A9 |
Wentworth; Steven W. ; et
al. |
March 15, 2018 |
Slip Style Rod Spinner For Pipe Bursting Machine
Abstract
A system for pushing and pulling rod strings through the ground
or an underground pipe. The apparatus has a downhole tool attached
to the distal end of the rod string. The push/pull machine has a
stationary frame that is placed against the ground to provide a
reaction surface. The stationary frame has an opening for the rod
string to pass through. A rod gripping assembly is supported on the
machine frame and moveable relative to the stationary frame. The
push/pull machine has a powered rod section spinner to add or
remove rod string sections from the rod string. An actuator powers
movement of jaws into a spinner bowl to cause a powered gripping of
the rod string section. With the rod string section gripped a motor
is activated to rotate the rod string section to connect it to a
rod string or disconnect it from the rod string.
Inventors: |
Wentworth; Steven W.;
(Fountain Hills, AZ) ; Crane; Robert F.;
(Oconomowoc, WI) ; Thompson; Walter George;
(Janesville, WI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Earth Tool Company LLC |
Oconomowoc |
WI |
US |
|
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20150252632 A1 |
September 10, 2015 |
|
|
Family ID: |
54016866 |
Appl. No.: |
14/512717 |
Filed: |
October 13, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61949112 |
Mar 6, 2014 |
|
|
|
61949454 |
Mar 7, 2014 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 19/086 20130101;
E21B 19/00 20130101; E21B 7/30 20130101; E21B 19/08 20130101; E21B
17/00 20130101; E21B 19/06 20130101 |
International
Class: |
E21B 19/00 20060101
E21B019/00; E21B 17/00 20060101 E21B017/00; E21B 19/08 20060101
E21B019/08; E21B 19/06 20060101 E21B019/06 |
Claims
1. An apparatus for pushing and pulling a rod string, the rod
string comprising a plurality of rod string sections connected
together end-to-end, the apparatus comprising: a downhole tool
connected to a first end of the rod string; a frame having a first
end and a second end; a stationary frame supported at the first end
of the frame, the stationary frame comprising an opening for the
rod string to pass through into the ground; a thrust assembly
supported by the frame and movable along the frame from the first
end to the second end, wherein the thrust assembly comprises a main
slip-bowl to grip the rod string to push and pull the rod string
through the ground; and a rod spinner supported at a second end of
the frame, the rod spinner comprising: a gripper movable between a
gripping position and a non-gripping position; the gripper being
disposed around a rod string section to be added or removed from
the rod string; a driven member connected to the gripper to cause
the gripper to rotate with the driven member; and a drive member
connected to the driven member to drive rotation of the driven
member, the gripper and the rod string section supported within the
gripper in both clockwise and counterclockwise directions to thread
the rod section onto the rod string or to unthread the rod section
from the rod string.
2. The apparatus of claim 1 wherein the thrust assembly comprises a
thrust cylinder to push and pull the rod string through the
ground.
3. The apparatus of claim 2 wherein the stationary frame comprises
a reaction plate to disperse force generated by the thrust
cylinder.
4. The apparatus of claim 1 wherein the rod spinner comprises a
cylinder to move the gripper between the gripping position and the
non-gripping position.
5. The apparatus of claim 2 further comprising a rail engaged with
the stationary frame, wherein the thrust assembly is movable toward
and away from the stationary frame on the rail in response to
operation of the thrust cylinder.
6. The apparatus of claim 1 wherein the gripper comprises: a
spinner bowl affixed to the driven member, the spinner bowl having
a conical inner surface; and a pair of jaws comprising a gripping
surface slidably supported within the spinner bowl to grip the rod
string section when the jaws are moved toward an end of the conical
inner surface having a smaller circumference.
7. The apparatus of claim 6 wherein the spinner bowl comprises a
plurality of tracks and wherein the pair of jaws is disposed on the
tracks.
8. The apparatus of claim 6 wherein the pair of jaws comprise a
dovetail formed on a side of the jaws opposite the gripping
surface, the spinner bowl comprising a pin formed to interlock with
the dovetail.
9. The apparatus of claim 1 wherein driven member comprises a ring
sprocket, wherein the gripper is affixed within the ring sprocket
for rotation therewith.
10. The apparatus of claim 9 further comprising a motor to cause
rotation of the driven member in both clockwise and
counterclockwise directions.
11. The apparatus of claim 1 further comprising: a spinner bowl
supported by the driven member, the spinner bowl having an opening
with a greater diameter at a first end and a lesser diameter at a
second end; a pair of jaws disposed within the opening of the
spinner bowl and to surround the rod string section disposed within
the opening; a thrust member aligned with the opening of the
spinner bowl, wherein the pair of jaws are connected to the thrust
member; and an actuator to move the thrust member and pair of jaws
relative to the spinner bowl to push the pair of jaws into the
spinner bowl toward the first end of the spinner bowl to cause the
jaws to grip the rod string section.
12. A rod spinner for adding and removing a rod string section from
a rod string used in pipe-bursting operations, the rod spinner
comprising: a gripper movable between a gripping positions and a
non-gripping position, the rod string section being disposed within
the gripper and the gripper being in the gripping position when the
rod string section is threaded onto the rod string or unthreaded
from the rod string; an actuator to move the gripper between the
gripping position and the non-gripping position; a driven member
affixed to the gripper to cause the gripper to rotate with the
driven member; and a drive member connected to the driven member to
rotate the driven member, the gripper, and the rod string section
disposed within the gripper in both clockwise and counterclockwise
directions to thread the rod section onto the rod string or to
unthread the rod section from the rod string.
13. The rod spinner of claim 12 wherein the gripper comprises: a
spinner bowl supported by the driven member, the spinner bowl
having an opening with a greater diameter at a first end and a
lesser diameter at a second end; a pair of jaws disposed within the
opening of the spinner bowl to surround the rod string section
disposed within the opening; a thrust member aligned with the
opening of the spinner bowl, wherein the pair of jaws engage the
thrust member; and an actuator to move the thrust member and pair
of jaws relative to the spinner bowl to push the pair of jaws into
the spinner bowl toward the first end of the spinner bowl to cause
the jaws to grip the rod string section.
14. The rod spinner of claim 13 wherein the actuator moves the
thrust member away from the spinner bowl to partially withdraw the
pair of jaws from the opening to cause the pair of jaws to release
the string section.
15. The rod spinner of claim 12 wherein the thrust member rotates
with the driven member.
16. The rod spinner of claim 12 wherein the gripper comprises: a
spinner bowl affixed to the driven member, the spinner bowl having
a conical inner surface; and a pair of jaws comprising a gripping
surface disposed within the spinner bowl and slidably supported
within the spinner bowl to grip the rod string section when the
jaws are moved toward an end of the conical inner surface having a
smaller circumference.
17. The rod spinner of claim 16 wherein the spinner bowl comprises
a plurality of tracks and wherein the pair of jaws is disposed on
the tracks.
18. The rod spinner of claim 16 wherein the pair of jaws comprises
a dovetail formed on a side of the jaws opposite the gripping
surface, the spinner bowl comprising a pin formed to interlock with
the dovetail.
19. The rod spinner of claim 12 wherein driven member comprises a
ring sprocket, wherein the gripper is affixed within the ring
sprocket for rotation therewith.
20. The rod spinner of claim 19 further comprising a motor to cause
rotation of the driven member in both clockwise and
counterclockwise directions.
21. A method for the replacement of an underground pipe, the method
comprising: wedging a rod string within a main slip-bowl of a
thrust assembly; positioning a rod string section to be added to a
proximate end of the rod string within a rod spinner and in an
engaging orientation with the rod string; wedging the rod string
section within a spinner bowl of the rod spinner a pair of jaws;
actuating a spinner motor to rotate the rod string section relative
to the rod string to connect the rod section to the rod string so
that linear and rotational forces may be transmitted from the rod
section to the rod string; at least partially withdrawing the pair
of jaws from the spinner bowl to release the rod section; and
moving the thrust assembly to advance the rod string through the
ground.
22. The method of claim 21 further comprising: advancing the rod
string and the rod section into the ground by actuating a main
thrust cylinder; releasing the rod string from the main slip-bowl;
and reversing the main thrust cylinder to move the thrust assembly
rearward along the rod string.
23. The method of claim 21 further comprising: thrusting the rod
string into the underground pipe until a distal end of the rod
string reaches a target point; connecting a downhole tool and a new
pipe to the distal end of the rod string; repeatedly gripping and
releasing the rod string to pull the rod string until it is removed
from the underground pipe and the new pipe has replaced the
underground pipe; and removing rod string sections from the rod
string by actuating the spinner to rotate an uphole rod string
section relative to the rod string to unthread the rod string
section from the rod string.
24. The method of claim 21 wherein the rod string section comprises
activating an actuator to move the pair of jaws to a gripping
position within the spinner bowl.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of provisional patent
application Ser. No. 61/949,112, filed on Mar. 6, 2014 and
provisional patent application Ser. No. 61/949,454, filed Mar. 7,
2014, the entire contents of which are incorporated herein by
reference.
FIELD
The present invention relates generally to machines for pushing and
pulling rod strings through the ground and specifically to machines
used to replace underground pipe and utilities.
SUMMARY
[0002] The present invention is directed to an apparatus for
pushing and pulling a rod string. The rod string comprises a
plurality of rod string sections connected together end-to-end. The
apparatus comprises a downhole tool, a frame, a stationary frame, a
thrust assembly, and a rod spinner. The downhole tool is connected
to a first end of the rod string. The frame has a first end and a
second end. The stationary frame is supported at the first end of
the frame and comprises an opening for the rod string to pass
through into the ground. The thrust assembly is supported by the
frame and movable along the frame from the first end to the second
end. The thrust assembly comprises a main slip-bowl to grip the rod
string to push and pull the rod string through the ground. The rod
spinner is supported at a second end of the frame. The rod spinner
comprises a gripper, a driven member, and a drive member. The
gripper is movable between a gripping position and a non-gripping
position and is disposed around a rod string section to be added to
or removed from the rod string. The driven member is connected to
the gripper to cause the gripper to rotate with the driven member.
The drive member is connected to the driven member to cause
rotation of the driven member, the gripper, and the rod string
section supported within the gripper in both clockwise and
counterclockwise directions. Rotation of these components together
will thread the rod section onto the rod string or unthread the rod
section from the rod string.
[0003] The present invention is directed to a rod spinner for
adding and removing a rod string section from a rod string used in
pipe-bursting operations. The rod spinner comprises a gripper, an
actuator, a driven member, and a drive member. The gripper is
movable between a gripping position and a non-gripping position.
The rod string section is disposed within the gripper and the
gripper is in the gripping position when the rod string section is
threaded onto the rod string or unthreaded from the rod string. The
actuator moves the gripper between the gripping position and the
non-gripping position. The driven member is affixed to the gripper
to cause the gripper to rotate with the driven member. The drive
member is connected to the driven member to rotate the driven
member, the gripper, and the rod string section disposed within the
gripper in both clockwise and counterclockwise directions to thread
the rod section onto the rod. string or to unthread the rod section
from the rod string.
[0004] The present invention is likewise directed to a method for
the replacement of an underground pipe. The method comprises
wedging a rod string within a main slip-bowl of a thrust assembly.
A rod string section to be added to a proximate end of the rod
string is positioned within a rod spinner and in an engaging
orientation with the rod string. A rod string section is wedged
within a spinner bowl of the rod spinner in a pair of jaws. A
spinner motor is actuated to rotate the rod string section relative
to the rod string to connect the rod section to the rod string so
that linear and rotational forces may be transmitted from the rod
string section to the rod string. The pair of jaws is at least
partially withdrawn from the spinner bowl to release the rod
section and the thrust assembly is moved to advance the rod string
through the ground.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a diagrammatic representation of one use of the
rod gripping mechanism of the present invention in a utility
installation operation.
[0006] FIG. 2 is an isometric view of a rod pushing/pulling machine
with the external housing and hydraulics removed.
[0007] FIG. 3 is an isometric illustration of a rod spinner of the
machine of FIG. 2.
[0008] FIG. 4 is longitudinal section view of the rod spinner
assembly of FIG. 3.
[0009] FIG. 5 is longitudinal section view of the rod spinner
assembly of FIG. 4 with the yoke member extended.
[0010] FIG. 6 is a cross-section view of the rod spinner of FIG. 5
along line 6-6.
DESCRIPTION
[0011] As the infrastructure of underground utilities has aged the
need to replace these underground utilities has grown. However,
home and business owners do not like to have their landscaping and
streets dug up during the replacement of underground utilities.
Thus, systems and methods for the replacement of underground
utilities with minimal surface disruption have been developed. For
example, horizontal directional drills are regularly used to
install new utilities and replace old utilities. Another technology
widely used are pit launched rod pushing and pulling machines.
These machines push a rod string, comprised of a series of rod
string sections attached end-to-end, through an existing pipeline
from a launch pit to an exit point remote from the machine.
Sections of rod are added to the rod string as the rod string is
pushed into the pipe. Conversely, rod string sections are removed
from the rod string as the new utility is pulled into the ground
toward the launch pit.
[0012] One skilled in the art will appreciate that a downhole tool
comprising a drill bit could be attached to the far end of the rod
string to allow the rod string to be pushed through the ground or
an existing pipe. Once the far end of the rod string reaches the
target point a downhole tool such as a backreamer or pipe splitter
may be attached to the far end of the rod string. The new pipe to
be installed may be connected to the downhole tool so that the new
pipe follows the downhole tool back through the ground or old pipe
to the launch pit. The machine grips the rod string and, using
hydraulic cylinders, pulls the rod string, downhole tool, and new
pipe toward. the launch pit. The downhole tool may comprise a pipe
bursting head configured to either burst or slice the old pipe and
push it into the surrounding soil.
[0013] Threaded pipe or rod strings are generally used in vertical
and horizontal drilling and particularly in pipe bursting. The pipe
sections range in length from a section of two feet to over fifteen
feet in oil and gas operations. High tensile loads are applied to
rod strings, whether they are hung vertically in a miles deep bore
or deployed horizontally in a pipe burst.
[0014] Oil rigs use gravity assisted slips to hold the downhole
tool off the bottom of the bore, such as when tripping out to
change the drilling tooling, or to provide torsional restraint when
adding or removing the top pipe from the string. Gravity assisted
slips have a heavy walled outer slip bowl, slips, and jaws. The
slip bowl is generally mounted on a structure that passes reaction
forces to the ground. The slip bowl is ring shaped and has a
conical inside surface running for its functional length; both ends
of the bowl are open. The pipe or rod string is disposed at
cylindrical centerline of the slip bowl, The angle of the conical
side relative to the centerline is on the order of five (5) to
fifteen (15) degrees with a preferred angle of ten (10) degrees per
side. Without the slips engaged with the rod string, the rod string
is free to move in either direction along the axial centerline.
Slips are generally thin walled segments having a conical surface
on a first side and a cylindrical surface on a second side. The
conical surface of the slip is configured to slide with low
friction against the conical inner surface of the slip bowl. The
cylindrical inner surface of the slip is intended to produce a high
coefficient of friction against the matching cylindrical surface of
the rod and may have a hardened and serrated finish intended to
bite into the mating rod surface. The inner surface is the jaw and
may be a replaceable component within the slip. There are generally
a minimum of two slips and often there are more, up to a dozen.
[0015] In oil field applications, gravity causes the slips to drop
into the tapered annular space between slip bowl and the rod. This
causes friction between the rod and the slips. As the rod string
moves down under the force of gravity the slip moves with it deeper
toward the small diameter end of the slip bowl. Movement continues
until at least two opposing slips apply normal forces to the slip
bowl cone and the rod string. At this point the rod will be
centered in the bowl and both the normal forces and the friction
forces of the engaged components rise quickly with slight distances
of rod string travel.
[0016] The rod string and slips move deeper into the slip bowl
until the friction forces on the rod string are equal in magnitude
and opposite in direction to the weight (or other) forces pulling
the rod string and causing movement. The rod will stop when the
normal force around the bowl has caused the bowl to grow slightly
within its elastic nature allowed by the geometry of all the
components involved adjacent to and including the slip bowl. The
invention disclosed in co-pending U.S. patent application Ser. No.
14/242,546 filed Apr. 1, 2014, and entitled. "Powered Slip
Actuation", the contents of which are fully incorporated herein,
provides a system to induce slip movement toward the small end of
the main slip bowl without requiring the force of gravity. Such a
system helps lead to successful clamping of the rod string in
either the vertical or horizontal orientation. The system of the
present invention provides a similar powered gripping system that
may be used in conjunction with the invention disclosed in the
above-referenced patent application to clamp a rod string section
within a rod spinner for powered addition or removal of rod string
sections from the rod string gripped by the main slip bowl.
[0017] Turning now to the figures, FIG. 1 shows a rod
pushing/pulling machine generally referred to herein as a thrust
unit 10 intended for pipe bursting. The thrust unit 10 is connected
to a rod string 12 for pushing into the ground or an existing pipe
14 and pulling back a downhole tool 16 and a new pipe 18. As shown,
the downhole tool 16 may comprise a pipe burster and swivel for
connecting the downhole tool to the new pipe 18. The downhole tool
16 is connected to a first end 20 of the rod string. A second end
22 of the rod string is connected to the thrust unit 10. The rod
string 12 may be threaded, or may be hooked together by turning or
fitting pipe sections together. In accordance with the present
invention, the rod string sections 23 are threaded together. One
skilled in the art will appreciate that the process of pushing the
rod. 12 into the existing pipe 14 will require thrust force.
[0018] Turning now to FIG. 2, the thrust unit 10 is shown with rod
string 12. The thrust unit 10 comprises a frame 24 having a first
end 26 and a second end 28. As shown in FIG. 2, the frame 24 may
comprise a pair of rails. A stationary frame 30 is supported at the
first end 26 of the frame 24. The stationary frame 30 comprises an
opening 32 for the rod string 12 to pass through into the old pipe
and the ground. A thrust assembly 34 is supported by the frame 24
and movable along the frame from the first end 26 to the second end
28. The thrust assembly 34 comprises a main slip-bowl 36 to grip
the rod string 12 to push or pull the rod string through the old
pipe and the ground.
[0019] The thrust assembly 34 is movable along the rails 24
relative to the stationary frame 30. The thrust assembly 34
comprises the main slip-bowl 36, two thrust cylinders 38, two rams
40, and rod spinner 42. As shown, the thrust assembly 34 comprises
wheels 44 for interaction with the rails 24. One of ordinary skill
will appreciate that rack-and-pinion, pulley, or other systems are
appropriate alternatives for movement of the thrust assembly 34
relative to the stationary frame 30. Further, the thrust unit 10
may be operable with a different number of cylinders 38 and rams
40. Two cylinders 38 and rams 40 are chosen for convenience in the
figures and are not limiting on this invention. An appropriate
thrust unit for use with the present invention is disclosed in
co-pending and co-owned U.S. patent application Ser. No.
14/206,548, filed Mar. 12, 2014, and entitled "Stepped Load Pull
Back Using Rams" the contents of which are incorporated fully
herein.
[0020] As discussed above, the thrust assembly 34 comprises a main
slip-bowl 36 that travels toward and away from the stationary frame
30 as the thrust assembly 34 moves along the rails 24. The
cylinders 38 are connected to the thrust assembly 34 and the
stationary frame 30. Each cylinder 38 comprises a cylinder rod 46
that abuts the stationary frame 30. The cylinder rods 46 are
movable between a retracted and extended position in response to
the flow of hydraulic fluid to and from the cylinders 38. As shown,
cylinder rods 46 of the cylinders 38 are in the extended position.
The cylinders 38 expand and retract to increase or decrease the
distance between the stationary frame 30 and the thrust assembly
34, causing the rod string 12 to either push into the ground or be
pulled out of the ground. As shown, the cylinders 38 are diagonally
disposed about the thrust assembly 34 and therefore the rod string
12.
[0021] With continued reference to FIG. 2, the rams 40 provide
additional load when the cylinders 38 alone are insufficient. The
rams 40 comprise a contact surface or thrust nose (not shown) for
contacting the stationary frame 30. The rams 40 are hydraulically
actuated and mechanically retracted cylinders moveable between a
retracted and extended position in response to the flow of
hydraulic fluid. The rams 40 are attached at a first end to the
thrust assembly 34 but not attached to the stationary frame 30.
[0022] The rod spinner 42 threads on or off sections of the rod
string 12 to make up or break out the rod string during pushing or
pulling operations. A rod support frame 48 travels with the thrust
assembly 34 and maintains alignment between a rod section 23 (FIG.
1) about to be added and supports a newly removed rod section. The
rod spinner 42 is supported at the second end 28 of the frame
74.
[0023] The stationary frame 30 is a reaction plate that is
positioned to ground the machine 10 and allow the extension of the
cylinders 38 to cause the thrust assembly 34 to pull or push the
rod string. The rod string 12 travels through the central opening
32 and through the main slip-bowl 36 to the rod spinner 42. Jacks
(not shown) may be used to stabilize the stationary frame 30 to the
ground such that the operation of the thrust unit 10 does not cause
excessive movement in the stationary frame.
[0024] Turning now to FIG. 3, the rod spinner 42 is shown in detail
with other components of the machine stripped away for clarity. The
rod spinner 42 comprises a hydraulic cylinder 50 connected to a
frame plate 52 by bolts 54. Bolts 54 also connect cover plate 56 to
the frame plate 52. Two springs 58 are mounted to the frame plate
52 and extend parallel to a central axis 60 of the rod spinner. The
springs 58 permit the rod spinner 42 to float along the central
axis 60 as the rod string sections are connected or disconnected
from the rod string 12 (FIG. 2). A gripper 62, movable between a
gripping position and a non-gripping position, is supported within
the frame plate 52 and the cover plate 56. Hydraulic cylinder 50
moves the gripper 62 between the gripping position and the
non-gripping position. The gripper will be discussed in greater
detail below.
[0025] A hydraulic motor 64 is connected to the cover plate 56 and
has a drive shaft 136 (FIG. 6) that extends through an opening (not
shown) in the cover plate. Hydraulic motor 64 is used to rotate the
gripper 62 and the rod string section 23 held within the gripper to
connect or disconnect the rod string section from the rod string 12
(FIG. 2). Thus, it will be appreciated that hydraulic motor 64 may
drive rotation of the gripper 62 in both clockwise and
counter-clockwise directions. The hydraulic motor 64 is connected
to the cover plate 56 via a flange 66 and bolts 68. As shown in
FIG. 3, the bolt hole 70 for receiving bolt 68 may be slightly
oblong to allow for adjustment of the motor 64 relative to the
cover plate 56.
[0026] With reference to FIGS. 2 and 3, the springs 58 are
supported on a pair of horizontal lobes 72 formed on the frame
plate 52. Guide bars 74 are connected to the thrust frame 34 and
the frame plate 52 and function to maintain an alignment of the
central axis 60 of the gripper 62 with the central axis of the main
slip-bowl. The guide bars 74 are connected to the thrust assembly
34 using bolts 76 and connected to the frame plate 52 with bushings
118. A stop 78 is affixed to each guide bar 74 to maintain the
position of springs 58 against the frame plate 52 while allowing
the rod spinner 42 to float relative to the thrust assembly 34.
[0027] The gripper 62 comprises a pair of jaws 80 comprising a
gripping surface 82. Jaws 80 are supported within a spinner bowl 84
having a conical inner surface. Jaws 80 are slidably supported
within the spinner bowl 84 to grip the rod string section 23 (FIG.
2) when the jaws are moved toward an end 86 of the conical inner
surface of the spinner bowl along an inclined track 88. As shown in
FIG. 3, the spinner bowl 84 may comprise a plurality of inclined
tracks 88 on which the slips comprising jaws 80 are disposed.
Accordingly, slips supporting jaws 80 may comprise a dovetail 90
formed on a side of the slip opposite the gripping surface 82. The
corresponding track 88 may be angled to bring the jaws 80 closer
together as they move toward end 86. The track 88 comprises a pin
formed to interlock with the dovetail 90. Gripper 62 also comprises
a yoke 92 which will be described hereinafter.
[0028] Turning now to FIG. 4, the rod spinner 42 of FIG. 3 is shown
in a longitudinal sectional view to show the internal construction
and components of the rod spinner. The rod spinner 42 comprises the
gripper 62 and a driven member 94 connected to the gripper so that
the gripper rotates with the driven member. As discussed above, the
rod spinner 42 comprises an actuator that may comprise hydraulic
cylinder 50. Cylinder 50 may comprise a thrust cylinder that is
configured to push jaws 80 into the spinner bowl 84. The cylinder
50 comprises a thrust tube 96 having an access passage 98 to allow
a rod string section 23 to pass through the cylinder. The thrust
tube 96 is surrounded by a cylinder body 100 that is connected to
the frame plate 52 and may rotate relative to the cylinder body and
with the gripper 62. Cylinder body 100 may be affixed to the frame
plate 52. Alternatively, the cylinder body 100 may be connected to
the gripper 62 for rotation therewith, Cylinder piston 102 is
disposed within the cylinder body 100 and held within the cylinder
body by end cap 104. Bearings 106 and 108 disposed between the
cylinder piston 102 and the tube 96 provide bearing surfaces to
allow the tube to rotate relative to the body and end cap with
reduced friction. Bushings 110 keep the cylinder piston 102
aligned. and free to slide longitudinally relative to the cylinder
body 100 and end cap 104. When annular space 112 is pressurized
cylinder piston 102 is moved toward the left in FIG. 4. Likewise,
cylinder tube 96 is moved left with the piston 102 and engages the
jaws 80 to force the jaws into the spinner bowl 84 to grip the rod
string section 23 (FIG. 1) disposed therein. Pressurizing annular
space 114 forces the piston 102 and tube 96 back to the right to
its start position. This causes the jaws 80 to release its grip on
the rod string section.
[0029] Frame plate 52 comprises at least two lobes 72 having holes
116 formed therein. Bushings 118 are mounted on rods 74 (FIG. 2) to
connect rods 74 to the spinner 42 and hold springs 58. The rods 74
and bushings 118 allow the rod spinner 42 to move a short distance
along the rod string section. The springs 58 allow the rod spinner
42 to float as threads cause the rod string section to move away
from or toward the rod string as the rod string section is
connected to or disconnected from the rod string.
[0030] The driven member 94 comprising a ring gear or sprocket,
having a plurality of laterally extending teeth 120. Driven member
94 is disposed within the frame plate 52 and secured by the cover
plate 56 for rotation within the cavity created by the frame plate
and the cover plate. Bearings 122 are used within the cavity to
support rotation of the driven member 94 and align the hole 124
formed in the driven member with the access passage 98. Shear pins
126 secure the frame cover 56 to the frame plate 52 and maintain
alignment between the cover and the plate.
[0031] The spinner bowl 84 is affixed to the driven member 94
within the hole 124. The spinner bowl 84 has a conical inner
surface. The end 128 of spinner bowl 84 toward the cylinder 50 has
a larger diameter and the end 86 proximate the yoke 92 has a
smaller diameter. As discussed above, the spinner bowl 84 comprises
an angled track 88 that comprises a pin configured to engage with a
corresponding dovetail 90 (FIG. 3) formed on jaws 80. Set screws
130 may be used to secure the spinner bowl to the driven member 94
for rotation therewith.
[0032] Yoke 92 is coupled to the jaws 80 and is free to spin about
the central axis 60 when actuated by the motor 64. The yoke 92 may
be connected to the thrust tube 96 using threaded studs (not
shown). Thus, when the cylinder 50 is actuated and the thrust tube
96 moves to the left in FIG. 4, the yoke 92 will also move left
with the jaws 80. In FIG. 4, the yoke is shown separated only a
short distance from the cover plate 56. In this position, the jaws
80 are in the open or non-gripping position.
[0033] Turning now to FIG. 5, the rod spinner 42 is shown with the
gripper 62 in the gripping position. As shown the cylinder 50 has
been actuated to move jaws 80 into the gripping position. In
operation, annular space 112 is pressurized to move cylinder piston
102 and thrust tube 96 to the left in relation to the cylinder body
100 and the spinner bowl 84. The thrust tube 96 engages jaws 80 and
pushes them into the spinner bowl 84 along the inclined dovetail
pins 88 (FIG. 4). Actuation of the cylinder 50 in this manner also
causes the yoke 92 to extend from the cover plate 56. In accordance
with the present invention, once the jaws 80 have been moved to the
gripping position shown in FIG. 5, the motor 64 may be actuated to
drive rotation of the driven member 94. Rotation of the driven
member 94 in turn drives rotation of the spinner bowl 84, yoke 92,
jaws 80, thrust tube 96 and the rod string section 23 gripped by
the jaws. Rotation of these components may be in both the clockwise
and counterclockwise direction to thread the rod string section
onto the rod string or unthread the rod string section 23 from the
rod string 12 while the rod string is held by the thrust assembly
34 (FIG. 2).
[0034] Turning now to FIG. 6, the rod spinner of FIG. 5 is shown in
cross-section along line 6-6, In FIG. 6, springs 58 are shown
positioned on either side of cover plate 56. Cover plate 56 is
shown housing driven member 94 and a drive member 132. The cover
plate 56 may comprise a plurality of bolt holes 133 disposed about
the portion of cover plate that houses the driven member 94. Bolt
holes 133 are used to fasten the cover plate 56 to the frame plate
52 and the cylinder 50 to the frame plate. A lubrication port 135
may be formed in the top of cover plate 56 to allow for the
introduction of lubricant into the cavity created by cover plate 56
and frame plate 52. Bolt holes 137 disposed at the bottom of the
frame cover 56 are used to fasten motor 64 (FIG. 3) to the cover
plate.
[0035] The driven member 94 comprises a ring sprocket having a hole
124 to support the gripper 62 and a plurality of teeth 120. The
gripper 62 is affixed to the ring sprocket in the hole 124 for
rotation therewith. The gripper 62 is shown to comprise the spinner
bowl 84 and the jaws 80. FIG. 6 shows the spinner bowl 84 comprises
inclined tracks 88 formed as pins to interlock with the dovetail 90
formed on the side of the jaws 80 opposite the gripping surface of
the jaws. The jaws 80 slide along the inclined tracks 88 to move
the gripper between the gripping position and non-gripping
position.
[0036] The drive member 132 is shown disposed below the driven
member 94 and has a plurality of laterally extending teeth 134 that
engage teeth 120 of driven member. Drive member 132 comprise a
sprocket having a. drive shaft 136 that is driven by motor 64 (FIG.
3).
[0037] In operation, the rod string 12 is wedged into the main
slip-bowl 136 of the thrust assembly 34. A rod string section 23 to
be added to the proximate end 22 of the rod string 12 is positioned
within the rod spinner 42 and in an engaging orientation with the
rod string. The cylinder 50 is actuated to push jaws 80 into the
spinner bowl 84 to wedge the rod string section within the spinner
bowl 84. Next, the spinner motor 64 is actuated to rotate the rod
string section 23 relative to the rod string 12 to connect the rod
section to the rod string so that linear and/or rotation forces may
be transmitted from the rod string section to the rod string. The
cylinder 50 is actuated in the opposite direction to at least
partially withdraw the jaws 80 from the spinner bowl 84 to release
the rod string section. The thrust assembly 34 is then actuated to
advance the rod string 12 and the newly added rod string section
through the ground. The rod string 12 is advanced through the
ground by actuating the main thrust cylinders 38 to move the thrust
assembly along the frame 24. Once the cylinders 38 reach the end of
their stroke, the rod string is released from the main slip-bowl 36
and the thrust cylinders 38 are reversed to move the thrust
assembly 34 rearward along the rod string 12 and frame 24 to the
stationary position.
[0038] The rod string is thrust through the underground pipe 14
until the distal end 20 reaches a target point or exit pit. The
downhole tool 16 and new pipe 18 are connected to the distal end of
the rod string 12 and pulled toward the machine 10. The downhole
tool 16 and product pipe 18 are pulled by repeatedly gripping and
releasing the rod string with the thrust assembly 34 until the
downhole tool is removed from the underground pipe and the new pipe
has replaced the old underground pipe. Rod string sections are
removed from the rod string by gripping the terminal rod string
section and actuating the spinner 42 to rotate the terminal uphole
rod string section relative to the rod string to unthread the rod
string section from the rod string. The disconnected section is
removed from the machine and the thrust assembly resumes pulling
the rod string out of the ground.
[0039] Various modifications can be made in the design and
operation of the present invention without departing from the
spirit thereof Thus, while the principle preferred construction and
modes of operation of the invention have been explained in what is
now considered to represent its best embodiments, which have been
illustrated and described, it should be understood that the
invention may be practiced otherwise than as specifically
illustrated and described.
* * * * *