BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention provides a device and a method for manipulating tubular segments
for make up and installation of a tubular string in a well.
Description of the Related Art
[0002] Tubular strings installed in wells are made up by threadably coupling individual
tubular segments at a well site. For example, a string of drill pipe is made from
threadably coupling joints of drill pipe to rotate and advance a drill bit downhole.
A casing string is made up by threadably coupling casing segments to line a drilled
borehole to prevent collapse and to facilitate cementing. A production string is made
up and run through casing strings to provide a conduit from the formation to the surface
for producing oil or gas.
[0003] Valuable rig time is consumed in retrieving, positioning and threadably coupling
segments of pipe into a string. Since hundreds of segments may be made up and run
into a borehole, saving just seconds per connection results in a substantial savings
in rig time.
[0004] The amount of time required to engage and rotate the pipe segment and make up the
threaded connection to the pipe string is only a portion of the rig time consumed
in making a connection. The time consumed in obtaining and positioning each add-on
segment atop the string for make up is determined in part by the efficiency of tools
used to retrieve and manipulate the segment.
[0005] Tools are available for manipulating and positioning segments for make up into a
string. Existing tools typically consist of a single joint elevator suspended by a
rope slung beneath a main string elevator. Suspending the single joint elevator by
a rope imposes many limitations on the efficiency of the process of adding pipe segments
to the pipe string. These existing systems require rig personnel to swing or carry
the single joint elevator to the receiving door and place it onto the pipe segment
to be added onto the string. Also, once the pipe segment is coupled to the rope and
hoisted above the rig floor, the pipe segment will generally not hang vertical due
to the force of gravity, and it is difficult and awkward to maneuver the pipe segment
into a vertical position atop the pipe string suspended in the borehole. Finally,
once the pipe segment is threadably coupled to the pipe string in the borehole, the
single joint elevator must be removed from the path of the string elevator or top
drive, and rig personnel are required to carry the elevator back to the receiving
door or other location on the rig floor.
[0006] An improved method and apparatus are needed for manipulating segments to be made
up into a pipe string. The method and apparatus would preferably provide more precise,
safe and efficient manipulation of segments and save time in making up the string.
The apparatus would preferably be light-weight, so that it can be easily removed from
the path of the string elevator or top drive, but sufficiently robust to support and
manipulate tubular segments.
SUMMARY OF THE PRESENT INVENTION
[0007] One embodiment of the present invention comprises a single joint manipulator arm
having a swing arm supporting a single joint elevator for securing a pipe segment
to the swing arm. The swing arm is a strong and generally light-weight arm positionable
with one or more cylinders or other actuators for rotatably aligning the segment with
the string. In a first embodiment, the present invention provides a single joint manipulator
arm that is pivotably securable to one or more bails that support a string elevator
for lifting and lowering the pipe string into the borehole after each joint or stand
of new pipe is threadably coupled into the string. The present invention provides
a light-weight single joint manipulator arm that is easily and efficiently removed
from the path of the string elevator or spider elevator. In a second embodiment, the
present invention provides a single joint manipulator arm that is pivotably securable
to a sub threadably coupled to a top drive shaft or quill. In this embodiment, the
manipulator arm is pivotably secured to the sub above other components, such as a
fill-up and circulation tool, or it is pivotably secured to a sub positioned below
a top drive shaft and above a casing running tool.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Fig.
1 is a side elevation view of one embodiment of a single joint manipulator arm of the
present invention in its aligned position and suspended from the bails on a rig.
[0009] Fig.
2 is a side elevation view of the single joint manipulator of Fig.
1 in its removed or "luffing" position.
[0010] Fig.
3 shows the single joint manipulator arm of Fig.
1 coupled to a casing segment at the staging area.
[0011] Fig.
4 shows the single joint manipulator arm of Fig.
1 after the bails and the string elevator are elevated and the single joint manipulator
arm and casing segment controllably rotated clockwise from its position shown in Fig.
3.
[0012] Fig.
5 is a side elevation view of the single joint manipulator arm of Fig.
1 after the bails and the string elevator are elevated from the position in Fig.
4, and the single joint manipulator arm and casing segment controllably rotated further
clockwise to suspend the casing segment adjacent to the axis of the well.
[0013] Fig.
6 is a side elevation view of the single joint manipulator arm of Fig.
1 after being rotated further clockwise from its adjacent position shown in Fig.
5 to generally suspend the segment in a vertical position aligned with the string in
the well.
[0014] Fig.
7 is a side elevation view of the single joint manipulator of Fig.
1 illustrating a safety fuse used for preventing tool failure from excessive load being
applied.
[0015] Fig.
8 is a perspective view of the single joint manipulator arm of Fig.
1 showing a bifurcated pivoting attachment to the bails and powered rotation using
a pair of actuators.
[0016] Fig.
9 is a perspective view of a modified lower portion of the single joint manipulator
arm of the present invention comprising a slew actuator for angular displacement of
the stand-offs to position a tubular segment secured within the single joint elevator.
[0017] Fig.
10 is a perspective view of an alternative embodiment of the single joint manipulator
arm of the present invention pivotably supported by a sub that is threadably coupled
to and suspended from a top drive. The sub also supports a casing running tool that
is operated by the top drive to releasably engage and support the pipe string and
a fill-up and circulation tool.
[0018] Fig.
11 is a perspective view of another alternative embodiment of the single joint manipulator
arm of the present invention pivotably supported by a sub that is threadably coupled
to and suspended from a top drive. The sub supports a fill-up and circulation tool
that is aligned with the top drive and positioned to enter the proximal end of a pipe
string secured within the string elevator.
[0019] Fig.
12 is a high-level method flowchart describing one embodiment of a method of the present
invention.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
[0020] The present invention provides an apparatus and method for manipulating casing segments
to assemble a casing string in a borehole. A single joint manipulator arm may be used
to safely and reliably manipulate casing segments as they are made up into a casing
string and installed in a well. The embodiments disclosed below describe the manipulation
of casing segments to assemble a casing string using the present invention. It is
to be understood, however, that other types of tubular segments, including drill pipe
and production tubing, may be similarly manipulated to assemble strings without departing
from the scope of the invention. For the reason, the terms "pipe", "tubular" and "casing"
are used interchangeably, as are the terms "segment" and "joint."
[0021] In one embodiment, an apparatus and method of the present invention are used to assemble
and run a casing string. Once assembled, the casing string will include a plurality
of casing segments threadedly coupled end-to-end and installed in a well. The rig
on which this embodiment may be used includes a hoist movably suspending a pair of
bails that, in turn, suspend a string elevator. A swing ann, having a proximal end,
and a distal end is pivotally coupled at its proximal end to the bails at a location
above the string elevator. The swing arm supports a single joint elevator at its distal
end, which may be a hinged-body type elevator or a horseshoe elevator. The pivoting
swing arm is angularly positionable relative to the bails using one or more actuators,
such as cylinders. Control of the swing arm and the hoist enable the operator to efficiently
retrieve a casing segment from a staging area and to move the casing joint into abutting
alignment with the string for being threadably coupled into the string.
[0022] A segment of large casing to be lifted using the manipulator arm may weigh 2,000
pounds (980 kg). A casing string may weigh 400,000 pounds (181,600 kg). The string
elevator is very heavy compared to the single joint manipulator arm, and the moment
imposed on the bails by the light-weight single joint manipulator arm and the casing
segment do not significantly deflect the string elevator and the heavy bails from
the vertical orientation.
[0023] Fig.
1 is a side elevation view of one embodiment of a single joint manipulator arm
10 the present invention. A perspective view of this same embodiment is shown in Fig.
8. A string elevator
12 is secured to a pair of bails
14, 114 at lifting ears
16, 116. The string elevator
12 is sized and configured for coupling to and supporting a casing string by securing
the proximal end of the casing string (not shown in Figs.
1 or
8 - see element
36 in Figs.
3-6). The bails
14, 114 are configured for supporting the weight of the string elevator and the casing string,
and are coupled at their supported ends to a block suspended by a draw works (not
shown).
[0024] The single joint manipulator arm
10 of the present invention comprises a swing arm
18 pivotally coupled at swing arm pivots
28b, 128b to bails
14, 114. The swing arm
18 includes an upper portion
20 that forms an angle to the swing arm and provides offset clearance around the string
elevator
12 when the swing arm
18 is generally vertical (see Fig.
6). Single joint elevator
22 is supported from stand-off members
52 and
152 pivotally coupled to the distal end
17 of the swing arm
18 for releasably securing and supporting a casing segment (not shown in Figs.
1 and
8 see Figs.
3-6).
[0025] Typically, an internally threaded coupling is used to threadably coupled two casing
segments end-to-end. This coupling structure provides an external circumferential
shoulder that a single joint elevator
22 may engage to support the add-on casing segment. However, it is within the scope
of the present invention to use a single joint elevator adapted for securing integral
connection segments by clamping along the length of the body of the pipe segment in
place of the horseshoe elevator shown in Fig.
1 or the hinged-body type elevator shown in Fig.
9. The string elevator, horseshoe elevator and hinged-body type elevator shown in the
drawings are included in the disclosed embodiment of the present invention for illustration
only.
[0026] The generally light-weight swing arm
18 of the single joint manipulator arm of the present invention may be extendable, such
as by axially telescoping. As shown in Figs.
1 and
8, the length of the swing arm
18 may be adjustable in length by telescoping an inner beam member
26 from within an outer beam member
24, then securing the outer and inner beam members
24, 26 by, for example, inserting a pin
28 through a pair of alignable holes
27. The use of tubular or squared tubular steel may provide a good strength to weight
ratio.
[0027] The swing ann
18 is controllably rotatable about the pivots
28b, 128b using an actuator, such as a pair of pneumatic or hydraulic cylinders
21, 121. The cylinders
21, 121 each comprise a piston (not shown) coupled to selectively extendable and retractable
rods
23, 123, respectively, that are axially positionable with respect to cylinders
21, 121. The rods
23, 123 in Figs. 1 and
8 arc shown in the extended condition to position the swing arm
18 in a substantially vertical position generally parallel to the bails
14, 114.
[0028] Fig.
2 is a side elevation view of the single joint manipulator arm
10 in a substantially horizontal or luffing position. The rods
23 and
123 (the latter not shown in Fig.
2) are shown retracted into the cylinders
21 and
121 (the latter not shown in Fig.
2) to position the swing arm
18 generally perpendicular to the bails
14 and
114 (the latter not shown in Fig.
2). The luffing position illustrated in Fig.
2 serves two purposes. Casing segments are sometimes presented to the rig floor at
a receiving door in a substantially horizontal condition. The luffing position shown
in Fig.
2, or a position near horizontal, may be suitable for coupling the elevator
22 supported by the single joint manipulator arm
10 to casing segments presented in this condition. Also, the luffing position removes
the single joint manipulator arm
10 and the supported elevator
22 from obstructing the full descent of the string elevator
12 (or, in other embodiments, a casing running tool or a top drive) as it lowers a casing
string into the borehole after an add-on casing segment is made up into the casing
string.
[0029] Receiving doors, or staging areas, on some rigs present add-on pipe segments to the
rig floor in a position angled between vertical and horizontal (see Fig.
3). In use on these rigs, the cylinders
21 and
121 (the latter not shown in Fig.
3) may be used to position the elevator
22 supported by the single joint manipulator arm
10 to a suitable angled position between vertical and horizontal for coupling to the
presented casing joint
30. When the single joint manipulator arm
10 is moved to the desired initial position, a presented casing segment
30 is secured to the single joint manipulator arm
10 at the presented end
32 by securing the segment in the single joint elevator
22.
[0030] Figs.
3-6 are sequential side elevation views of the single joint manipulator arm
10 of Fig. 1 showing the process of manipulating a casing segment from an initial position
in a staging area (Fig.
3) to an aligned position for rotatably coupling to a casing string in a well (Fig.
6)
. To retrieve a casing segment from the staging area of a rig, an actuating member
first moves the swing arm outwardly away from vertical to position an end of the swing
ann in proximity to a staging area wherein casing joints are presented. Fig.
3 shows one embodiment of the single joint manipulator arm
10 in an initial position for retrieving a casing segment
30 from a rig staging area
35. The horseshoe elevator
22 is engaged just below a collar
32 of the presented casing segment
30. Once the segment is secured to the swing arm
18, the hoist raises the bails
14, 114 (the latter not shown in Fig.
3) the swing arm
18 and the casing segment
30. As the casing segment
30 is raised, it slides along ramp
37, and the swing arm
18 controllably rotates in the clockwise direction against the damping force of cylinders
21 and
121 (the latter not shown in Fig.
3). This clockwise rotation of the swing arm
18 against the damping force controllably moves the casing segment
30 in the direction of the casing string
34 (see Fig.
6). A damping member, such as a hydraulic, pneumatic or inert gas-charged cylinder, is
used to dampen and control movement of the swing arm as it rotates from the initial
position the equilibrium position. The damping member provides controlled and manageable
movement in manipulating the casing segment.
[0031] Fig.
4 is a side elevation view of the single joint manipulator arm
10 of Fig.
3 showing the bails
14 and
114 (the latter not shown in Fig.
3) elevated from their initial position shown in Fig.
3, and the single joint manipulator arm
10 rotated further clockwise against the damping force of the cylinders. The casing
segment
30 in Fig.
4 is shown substantially raised along ramp
37 from its initial position shown in Fig.
3. As the bails
14 and
114 (the latter not shown in Fig.
3) raise the single joint manipulator arm
10 and the casing segment
30 along ramp
37 in staging area
35, the weight of the casing segment
30 increasingly urges the swing arm
18 to rotate clockwise. The cylinders
21 and
121 (the latter not shown in Fig.
4) dampens the rate of clockwise swing of the swing arm
18, and the damping action provided by cylinders
21 and
121 will prevent rapid or uncontrolled swing of the casing segment
30 across the rig floor after the casing segment
30 clears the ramp
37.
[0032] Fig.
5 is a side elevation view of the single joint manipulator arm
10 of Figs.
3 and
4 showing the bails
14 and
114 (the latter not shown in Fig.
5) raised from the position shown in Fig.
4 and the swing arm
18 rotated further clockwise from its position shown in Fig.
4. The casing segment
30 shown in Fig.
5 hangs from single joint elevator
22 substantially vertically in an equilibrium position, but it is not aligned with the
casing string
34 in the well supported by the spider
36 because of the offset provided by the angled portion
20 at the top of the swing arm
18. As shown in Fig.
5, this equilibrium position is not aligned with the casing string
34, and the casing segment
30 hangs offset from alignment with the top connection with the casing string
34. The casing segment
30 hangs slightly suspended from the single joint elevator
22 like a pendulum, and the single joint elevator
22 imparts generally negligible torque on the casing segment
30. The equilibrium position of the swing arm
18 shown in Fig.
5 and the amount of offset is determined by the dimensions and weights of both the
single joint manipulator arm
10 and the casing segment
30 when cylinders
21 and
121 (the latter not shown in Fig.
5) are inactive. Since the casing segment
30 is generally significantly heavier than the swing arm
18, the casing segment
30 will generally hang near vertically below the pivots
28b and
128b (the latter not shown in Fig.
5) securing the pivot arm
18 to the bails
14 and
114 (the latter not shown in Fig.
5).
[0033] Fig.
6 is a side elevation view of the single joint manipulator arm
10 of Figs.
3-5 with the casing segment
30 vertically positioned above and axially aligned with the casing string
34, positioned to be lowered by the hoist (not shown in Fig.
6) to engage the casing string
34. The swing ann
18 has been rotated slightly further clockwise from its equilibrium position shown in
Fig.
5 by energizing the cylinders
21 and
121 (the latter not shown in Fig.
6) to extend the rods
23 and
123 (not shown in Fig.
6) to rotate the swing arm
18 from its equilibrium position of Fig.
5 to the aligned position shown in Fig.
6. Energizing the cylinders
21, 121 to extend the rods
23, 123 rotates the swing arm
18 further clockwise from its position shown in Fig.
5 and slightly vertically lifts the casing segment from its equilibrium shown position
of Fig.
5 as it vertically aligns the single joint elevator
22 and the casing segment
30 with the casing string
34. The capacity to rotate the single joint manipulator arm
10 clockwise from its equilibrium position shown in Fig.
5 provides substantially all of the rotational movement required to position casing
segment
30 may be alignment with the casing string
34. A lower, distal end
33 of the casing joint
30 is positioned to be threadably coupled with the proximal end of casing string
34. The string elevator
12 is substantially axially aligned with casing string
34 so that the hoist (not shown) and bails
14 and
114 may be lowered, along with the string elevator
12, to provide abutting contact for casing make up.
[0034] Once the casing segment
30 has been brought into aligned contact with the casing string
34, a power tong or other torquing device engages and axially rotates casing segment
30 to make up the threaded connection between the casing segment
30 and the casing string
34. After the connection is made, the single joint elevator
22 is released from the casing segment
30 and the swing arm
18 is rotated counterclockwise using cylinders
21 and
121 to its luffing position shown in Fig.
2. The hoist (not shown in Fig.
2) and bails
14 and
114 may then be lowered to bring the string elevator
12 to the proximal end
32 of the casing joint
30. The string elevator
12 may be engaged with the proximal end
32 of the casing segment
30, and the entire casing string
34 is lifted by the hoist (not shown) and the string elevator
12 to allow disengagement of the spider
36. The string elevator
12 is then lowered until the proximal end
32 of the casing segment
30 reaches the same elevation as previously occupied by the proximate end of the casing
string
34 shown in Fig.
6. The spider
36 is then engaged to support the casing string
34 in the well, and the string elevator
12 may be disengaged from the casing segment
30.
[0035] The process described above in connection with Figs.
3-6 is repeated with additional casing segments until the casing string
34 achieves the desired length.
[0036] To further enhance safety, the apparatus may include a safety fuse, such as a shear
pin, that will audibly shear if the swing arm supports a load that is substantially
heavier than a segment of the casing being made up and run into the well. Fig.
7 is a side elevation view of one embodiment of the single joint manipulator arm
10 for illustrating a load safety fuse
50. A pair of stand-offs
52, 152 (the latter not shown in Fig.
7) are secured at their first ends
52a, 152a (the latter not shown in Fig.
7) to the lower portion
17 of the swing arm
18 at pivot
54. A sacrificially failing safety link
58 is pivotally coupled to the swing arm
18 at pivot
58a located generally intermediate the pivotal coupling
54 of the stand-offs
52, 152 and angled portion
20. The safety link
58 is coupled between pivot
58a and shackle
57 which is, in turn, coupled to the first ends
56a, 156a of cables
56 and
156 (elements
156a and
156 not shown in Fig.
7 - see Fig.
8). The second ends
56b and
156b of cables
56 and
156 are coupled and supported to the second ends
52b and
152b of stand-off members
52 and
152. The safety link
58 generally is held by stand-offs
52, 152 at an angle to the swing arm
18. As shown in Fig.
7, that angle is about 20 degrees, with the stand-offs
52, 152 being supported substantially in positions perpendicular to the swing arm
18. The weight of the single joint elevator
22 biases the stand-offs
52, 152 generally downwardly when the single joint manipulator arm
10 is vertical, pulling cables
56 and
156 taut.
[0037] The safety link
58 comprises a sacrificially failing member that is designed to fail under a predetermined
load. Thus, the safety link
58 is designed to withstand the load produced in cables
56 and
156 when the weight of segment of casing is supported by the single joint elevator
22. A load significantly heavier than that of a casing segment plus the elevator
22 will cause the sacrificial member to fail, such as a shear failure, without dropping
the load. The sound of the sacrificial failure is loud enough to alert the rig operator.
In response to the sacrificial failure of the safety link
58, the stand-offs
52, 152 will slightly rotate about pivot
54 counterclockwise (in Fig.
7) but will remain coupled by safety link
58 to avoid dropping the casing segment coupled to the single joint elevator
22.
[0038] Fig.
8 is a perspective view of the embodiment of the single joint manipulator arm
10 in Figs.
1-7. The lifting ear
16 on the bail
14 is accompanied by a second lifting ear
116 on bail
114. These bails are movably suspended from a block (not shown), and are capable of supporting
very heavy loads, such as a casing string. The angled portion
20 of the swing arm
18 comprises a pair of generally parallel prongs
18a, 18b that are pivotally coupled to bail clamps
29, 129, respectively, at swing arm pivots
28b, 128b, respectively. The bail clamps
29, 129 are secured to bails
14, 114, respectively, using fasteners. The hydraulic cylinder
21 is accompanied by a second generally parallel hydraulic cylinder
121 for balanced damping of swinging loads applied to swing arm
18. The cylinders
21 and
121 comprise extendable and retractable piston rods
23, 123 that are pivotally coupled to swing ears
25, 125, respectively, of the swing arm
18. Cylinders
21, 121 are each pivotally coupled to bail clamps
29, 129, respectively, at pivots
28a, 128a, respectively. These pivoting cylinder couplings on bail clamps
29, 129 are each secured to the bails at a spaced distance above swing arm pivots
28b, 128b that pivotally secure the prongs
18a, 18b of swing arm
18 to the bail clamps
29, 129, respectively. The swing ears
25, 125 are offset from the swing arm so that pivoting of the swing arm
18 toward its equilibrium position (see Fig.
5) under the force of gravity rotates the swing ears
25, 125 away from the cylinders
21, 121 and requires substantial extension of the rods
23, 123 from cylinders
21, 121, respectively, for rotation. The resistance to extension of the rods
23, 123 from cylinders
21, 121 substantially dampens the rate of rotation of the swing arm
18 as compared to unrestrained swinging of the swing arm
18. Similarly, force imposed by powered retraction of rods
23, 123 into the cylinders
21, 121 pulls against swing ears
25, 125, respectively, to controllably rotate the swing arm
18 to the desired angular orientation, either to an initial position (see, for example,
Fig.
3) for coupling the single joint elevator
22 to a presented casing segment
30, or to the luffing position (see Fig.
2) for either coupling the single joint elevator to a horizontally presented casing
segment or for removing the swing arm
18 from obstructing the descent of the string elevator
12 to the spider
36.
[0039] In the embodiments discussed in connection with Figs.
1-8, hydraulic cylinders
21, 121 provide a dual function. According to a first function, the cylinders
21, 121 substantially slow and dampen movement of the swing arm
18 under the load of a casing segment secured in the elevator
22 as the single joint elevator and the load is lifted from a staging area. According
to a second function, cylinders
21, 121 are used as actuators to rotate the swing arm
18 beyond its equilibrium (shown in Fig.
5) to selectively position the swing arm
18 and thereby align the casing segment with the casing string, and also to rotate the
swing arm
18 to the luffing position or to an angle for securing the elevator to a presented casing
segment. Other embodiments may employ independent devices to actuate the swing arm
18 to align with the casing string and to dampen movement of the swing arm under load.
For example, it is within the scope of the present invention for one cylinder may
be used as an actuator to rotate the swing arm and another cylinder may used to dampen
swing rotation of the swing arm.
[0040] As previously mentioned, the swing arm
18 may comprise a telescoping portion. The outer beam
24 may slidably receive an inner beam
26. In other embodiments, a swing arm may be axially extendable without these beams being
concentric as in the embodiments of Figs.
1-8. For example, it is within the scope of the present invention for one beam to secure
to the other using a slot on one beam and a bolt or pin on the other beam that is
receivable and securable within the slot to lock the beams together to form a single
load-bearing member.
[0041] An advantage of an extendable swing arm is that it provides the ability to adjust
the length of the swing arm to manipulate different lengths of casing segments, to
adjust the single joint manipulator arm to cooperate with the height of the spider
at the rig floor, or generally to accommodate different drilling rig configurations.
Additional versatility is realized by use of the embodiments of the tool of the present
invention shown in Figs.
9-12. The single joint manipulator arm can be adapted for use with fill-up and circulation
tools, pipe gripping assemblies and slew actuators that enhance the capacity of the
tool to manipulate and position tubular segments for make-up into a tubular string.
[0042] Fig.
9 is a perspective view of a modified lower portion of the single joint manipulator
arm of the present invention comprising a slew actuator for angular displacement of
the stand-offs to position a tubular segment secured within the single joint elevator.
Fig.
9 shows an alternate embodiment of the single joint manipulator arm
10 of the present invention having enhanced capacity to manipulate and position tubular
segments supported in the single joint elevator
22. Fig.
9 shows a lower portion
20 of the single joint manipulator arm of the present invention equipped with a slew
actuator. A pair of stand-offs
52 and
152 are pivotally secured at their first ends
52a, 152a (the latter not shown in Fig.
9) to the lower portion
17 of the swing arm
18. The second ends
56b and
156b of cables
56 and
156 are coupled to the second ends
52b and
152b of stand-offs
52 and
152. The stand-offs
52, 152 are supported by cables
56 and
156 in positions generally perpendicular to the swing arm
18. The weight of the single joint elevator
22 and any tubular segment secured therein biases the stand-offs
52, 152 generally downwardly when the single joint manipulator arm
10 is vertical, thereby pulling cables
56 and
156 taut.
[0043] The enhanced capacity for manipulation and positioning of tubular segments provided
by the slew actuator shown in Fig.
9 is best understood by consideration of the ranges of controlled movement, relative
to a classic x-y-z three-dimensional coordinate system, provided by the single joint
manipulator arm. As seen in Figs.
3 - 6, the cylinders
21 and
121 provide controlled rotation of the swing arm
18 and the supported casing segment
30 in the x-y plane. This movement of the tubular segment
30 secured in the elevator
22 is primarily along the x-axis when the cylinders
21 and
121 position the swing arm
18 in the generally vertical orientations shown in Figs.
5 and
6. Vertical displacement of the tubular segment secured in the elevator
22 along the y-axis is provided by the rig hoist (not shown) that raises and lowers
the drawworks, block and the sub and/or bails to which the single joint manipulator
arm is secured. The slew actuator shown in Fig.
9 provides for controlled movement along the z-axis.
[0044] Fig.
9 shows the components of one embodiment of the single joint manipulator arm equipped
with a slew actuator providing enhanced positioning and manipulation of the suspended
tubular joint. The slew actuator housing
42 generally surrounds a slew actuator
43, which may be a cylinder, for positioning a slew rod
44 generally perpendicular to the pivotable stand-offs
52 and
152. While the actual movement of stand-offs
52 and
152 is radial about stand-off pivots
46a and
46b, respectively, the movement of a tubular segment (not shown in Fig.
9) secured in the elevator
22 upon actuation of the slew actuator
43 is substantially along the z-axis as defined above. Accordingly, this embodiment
of the present invention provides superior control and manipulation of casing segments
for being made up into a casing string.
[0045] Fig.
10 is a perspective view of one embodiment of the single joint manipulator arm
10 of the present invention secured to and supported by a top drive and supporting a
fill-up and circulation tool and a pipe gripping assembly. The single joint manipulator
arm
10 is pivotably secured to an enlarged portion of a sub
88 that is threadably coupled at its inlet
88a (above the sub
88) to a top drive and supports a casing running tool
104 from its discharge
88b (below the sub
88). In this embodiment, the discharge
88b of the sub
88 supports a casing running tool
104 having a gripping assembly sized for being received into a casing segment (not shown).
The casing running tool
104 comprises a plurality of pipe gripping shoes
105 that are deployable and retractable radially outwardly to grip and release the internal
wall of a casing segment to support the casing string or to rotate the casing segment
to make up the connection with the casing string.
[0046] The embodiment in Fig.
10 also comprises a fill-up and circulation tool
100 supported underneath the casing running tool. The elastomeric seal
103 is sized for engaging the internal wall of a casing string (not shown in Fig.
10) upon insertion. The seal enables pressurization of the casing string so that pressurized
fluid introduced into the bore of the casing string through the bore
101 of the fill-up and circulation tool
100 can be circulated down the casing string and back to the surface through the annulus
formed between the casing string and the borehole.
[0047] Fig.
11 is a perspective view of another embodiment of the present invention. The single
joint manipulator arm
10 of the present invention is secured to and supported by a top drive, and supports
a fill-up and circulation tool
100 comprising an elastomeric seal
103. A bore
101 formed by aligned bores in the top drive, sub
88 and the fill-up and circulation tool
100 provides a conduit for introducing fluid into the casing string. The single joint
manipulator arm
10 is pivotably secured to an enlarged portion of a sub
88 that is threadably coupled at its inlet
88a (above the sub
88) to a top drive and supports the fill-up and circulation tool
100 from its discharge
88b (below the sub
88). In this embodiment, a pair of bails
14, 114 is suspended from a support ring
89 that is rotatably supported by the top drive.
[0048] Fig.
12 is a flowchart describing one embodiment of a high-level method of manipulating casing
segment to assemble a casing string. In step
60, the swing arm is rotated to an initial position. A hydraulic cylinder or other actuator
is used to rotate the pivot arm away from vertical and to a desired angle according
to the orientation of a selected joint in the staging area. In step
62, the hoist is lowered as necessary to position a first elevator, such as a horseshoe
elevator, near a proximate end of the targeted casing segment. In step
64, the single joint elevator is coupled to the proximate end of the targeted joint.
In step
66, the hoist is raised to begin moving the joint into a suspended position. As the joint
is lifted along the ramp to leave the staging area, the swing arm rotates clockwise
toward an equilibrium position, and the rotation is dampened in step
68. Once the swing arm and the casing segment are substantially vertical and the joint
is suspended in the offset position, the joint is then aligned with the casing segment
by powered rotation of swing arm and lowered to abut the casing string in steps
70 and
72. Once the distal end of the joint is in contact with the upper end of the casing string,
the joint is threadably couplcd to the casing string in step
74. A power tong may be used to rotate the joint to threadedly couple the joint to the
casing string. Then, in step
76, the hoist is lowered while the single joint elevator is disengaged from the proximate
end of the joint. Lowering the hoist brings the string elevator near the proximate
end of the casing string and, in step
78, the string elevator engages the proximate end of that uppermost joint of the casing
string. In step
80, the casing string is lifted up slightly. This releases the load on the spider so
the spider is released according to step
82. In step
84, with the casing string released by the spider, the hoist is lowered to install the
casing string further into the borehole to about the position of the casing string
prior to connecting the additional joint in step
74. The spider slips are moved into contact with the casing string to support it in the
well. In the step
86, if the string has achieved the desired length, work stops. Otherwise the process
repeats as the swing are is rotated to an initial position in step 60.
[0049] Embodiments of the invention provide a safe and efficient way to assemble a casing
string. A highly maneuverable single joint manipulator arm retrieves a casing joint
from a variety of angles to access a staging area. The single joint manipulator arm
then positions the casing joint into alignment with the casing string in a controlled
manner using a damper. A casing string may also be assembled quickly and efficiently,
minimizing the time and expense associated with casing make up.
[0050] The terms "comprising," "including," and "having," as used in the claims and specification
herein, shall be considered as indicating an open group that may include other elements
not specified. The terms "a," "an," and the singular forms of words shall be taken
to include the plural form of the same words, such that the terms mean that one or
more of something is provided. The term "one" or "single" may be used to indicate
that one and only one of something is intended. Similarly, other specific integer
values, such as "two," may be used when a specific number of things is intended. The
terms "preferably," "preferred," "prefer," "optionally," "may," and similar terms
are used to indicate that an item, condition or step being referred to is an optional
(not required) feature of the invention.
[0051] The terms "segment." and "joint" are used interchangeably to refer to individual
portions of casing. The term "casing" is used to refer to casing, production tubing,
drill pipe and all other tubulars that may be coupled end-to-end and installed in
a well.
[0052] The present invention is a divisional application of
EP07842067.6. The original claims of
EP07842067.6 are presented as statements below.
- 1. An apparatus, for manipulating tubular segments for being made up into a tubular
string, the apparatus comprising:
a swing arm having a proximal end pivotally coupled to a hoist at a location above
a string elevator or a casing running tool;
an actuator pivotally secured to the swing arm for rotating the swing arm;
a damper pivotally secured to the swing arm, for damping rotation of the swing arm;
and
a single joint elevator secured to a distal end of the swing arm for releasably supporting
a tubular segment, the swing arm being rotatable to align the tubular segment with
another tubular segment to form a tubular string.
- 2.The apparatus of statement 1, wherein the actuator is a hydraulic or a pneumatic
cylinder.
- 3.The apparatus of statement 2, wherein the cylinder also functions as the damping
member.
- 4.The apparatus of statement I, wherein the damper comprises a hydraulic or a pneumatic
cylinder.
- 5.The apparatus of statement I, wherein the single joint elevator comprises a horseshoe
elevator or a hinged-body elevator.
- 6.The apparatus of statement 1, further comprising:
a sacrificially failing link coupled between the single joint elevator and the swing
arm, the single joint elevator being pivotable about the distal end of the swing arm
between a first position with the sacrificially failing link intact and a second position
assumed upon failure of the sacrificially failing link.
- 7.The apparatus of statement 6, further comprising:
a safety link pivotally secured to the swing arm with the sacrificially failing link
coupled to the safety link and also to the swing arm such that the safety link supports
the single joint elevator upon failure of the sacrificially failing link.
- 8.A method of making up a tubing string for installation in a borehole comprising:
suspending a string elevator on bails;
supporting a single joint elevator on a pivot arm pivotally secured to the bails at
a location above the string elevator;
rotating the swing arm to a first position wherein an axis of the single joint elevator
is substantially angularly misaligned from an axis of the string elevator;
engaging a proximate end of a tubing segment with the single joint elevator; and
rotating the swing arm to substantially align a distal end of the tubing segment with
a tubing string positioned in the well, while damping the rotation of the swing arm.
- 9.The method of statement 8, wherein damping the movement of the swing arm results
from moving a piston within a cylinder.
- 10. The method of statement 9, further comprising moving the swing arm to the luffing
position by energizing the cylinder.
- 11. The method of statement 10, wherein the luffing position is substantially horizontal.
- 12. The method of statement 8, further comprising one or both of raising and lowering
the string elevator and the single joint elevator using a hoist.
- 13. The method of statement 8, further comprising:
lowering the hoist to position the distal end of the tubing segment adjacent a proximate
end of the tubing string; and
threadedly coupling the distal end of the tubing segment with the proximate end of
the tubing string.
- 14.The method of statement 13, further comprising:
Rotating the swing arm to remove it from obstructing descent of the string elevator;
lowering the hoist to position the string elevator about the proximate end of the
tubing joint connected with the tubing string;
engaging the proximate end of the tubing segment with the string elevator;
raising the hoist and string elevator to at least partially unweight a spider supporting
the tubing string;
disengaging the spider from the tubing string;
lowering the hoist to install the tubing string further into the well; and
re-engaging the tubing string with the spider to support the tubing string in a the
well.
- 15. An apparatus for making up and installing a tubular string is a well comprising:
a vertically movable top drive;
a sub supported by the top drive and pivotably supporting a swing arm coupled to the
sub at its proximal end and coupled to a single joint elevator at its distal end;
an actuator for rotating the swing arm about its pivoting coupling to the sub between
a luffing position and an aligned position with the well; and
a damper for opposing swing rotation of the swing arm from the luffing position to
the aligned position.
- 16. The apparatus of statement 15 wherein the actuator is a hydraulic or pneumatic
cylinder.
- 17. The apparatus of statement 16 wherein the cylinder also functions as the damper.
- 18. An apparatus for manipulating tubular segments for being made up into a tubular
string and run into a well comprising:
a swing arm for pivotably coupling at its proximal end to a sub or bail above a string
elevator or casing running tool, the swing arm having a distal end coupled to a single
joint elevator;
an actuator for powered rotation of the swing arm between a removed position; an d
a damper for slowing the rotation of the swing arm from the removed position to the
aligned position.
- 19. The apparatus of statement 18 wherein the actuator is a pneumatic or hydraul ic
cylinder.
- 20. The apparatus of statement 19 wherein the cylinder also functions as the damper.
[0053] While the invention has been described with respect to a limited number of embodiments,
those skilled in the art, having benefit of this disclosure, will appreciate that
other embodiments can be devised which do not depart from the scope of the invention
as disclosed herein. Accordingly, the scope of the invention should be limited only
by the claims,