Patent Application
20160076327
Various types of fishing tools are used in wells to retrieve tools, tubulars, casing, or other components that become stuck in a well. In a typical technique, a drillpipe lowers a fishing tool into the well, and a grapple at the end of the tool engages the stuck component. An upward force on the drillpipe can then dislodge the component. In other techniques, jars that are hydraulically or mechanically powered can generate a jarring force to dislodge the stuck component.
For example, casing can become stuck in the well and may need to be retrieved. Traditional removal of the stuck casing is done either with pilot milling, pulling the casing free with jarring action, and then steady pulling applied through the drillpipe and the derrick's draw work. Milling is very time consuming and labor intensive. Additionally, using jars to deliver a retrieving force does not effectively retrieve mud stuck casing.
To deal with stuck casing, pulling tools or casing jacks, such as those available from HOMCO, Wilson Downhole, Houston Engineers, and others, have been used for some time in the past. As one example, a downhole force generating tool disclosed in U.S. Pat. No. 5,070,941 has an anchor and a piston/cylinder arrangement.
In another example, U.S. Pat. No. 8,365,826 discloses a hydraulically powered fishing tool that can be used to retrieve another tool or tubular stuck in a well. The fishing tool is supported in a well on a workstring and has a mandrel with a fishing device that engages stuck tool or tubular in the well. An anchor axially fixes the position of the tool in the well, and pistons disposed on the tool above the anchor move the mandrel so the fishing device on the end of the mandrel can be moved axially and can dislodge the stuck tool or tubular.
Older systems use anchoring and pulling that is much too weak to handle the pull loads experienced in wells today. Today, Wellbore A/S of Norway has developed a Down Hole Power Tool (DHPT) that uses the hydraulically powered fishing tool disclosed in U.S. Pat. No. 8,365,826 to retrieve casing. However, the fishing tool mentioned above has the anchor section disposed below the pull section. During operation, the pulling load must pass through the anchor section. Additionally, any torque that is needed to be transmitted downhole through the tool is done through the internal dimensions of the tool's members.
Although most stuck components, such as casing, can be dislodged using the above techniques and tools, some stuck components may require other means to be retrieved and may need techniques that avoid damaging the stuck component or other elements in the well.
The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.
A downhole pulling tool deploys on a workstring to retrieve a well component using an implement. The tool has a mandrel, an anchor, and a puller. The mandrel couples to the workstring, and the anchor is disposed on the mandrel. The mandrel can be a unitary component. For assembly purposes, however, the mandrel can include an anchor mandrel for the anchor coupled to a puller mandrel for the puller.
On the anchor, at least one slip is hydraulically actuated from an unset condition to a set condition. In this way, the at least one slip in the set condition can be wedged against a portion of the mandrel for engaging the anchor downhole in casing or tubing, for example. The puller, however, extends from the anchor and has at least one puller piston disposed on the mandrel. The at least one puller piston supports the implement and is hydraulically movable relative to the mandrel from an extended condition to a pulled condition.
The at least one slip in the set condition can extend outward from the mandrel and can retract inward toward the mandrel in the unset condition. For instance, the portion of the mandrel can define at least one ramped surface against which the at least one slip wedges.
The anchor has an anchor piston disposed on the mandrel. The anchor piston is hydraulically movable from a first condition to a second condition. According, the anchor piston in the second condition can wedge the at least one slip against the portion of the mandrel. To move the anchor piston, the mandrel defines a fluid passageway communicating with the workstring and conveying fluid to the anchor piston. A valve in the tool can then selectively communicate fluid conveyed through the fluid passageway to the anchor piston.
A number of biasing arrangements can be used to bias and control operation of the anchor, such as the operation of the at least one slip and the anchor piston. For example, the anchor piston can have at least one biasing element biasing the anchor piston to the first condition. The at least one biasing element can be a spring or the like having one portion engaged against the anchor mandrel and having an opposing portion engaged against the anchor piston.
In another example, the anchor piston can have at least one biasing element disposed between the anchor piston and the at least one slip. This biasing element can be a spring or the like having one portion engaged against the anchor piston and an opposing portion engaged against the at least one slip.
To help hold the at least one slip and control its movement relative to the mandrel, a cage can be disposed on the mandrel and can have the at least one slip movable therein. In this case, at least one biasing element can be engaged between the cage and the at least one slip and can bias the at least one slip to the unset condition. For example, the at least one biasing element can include first and second leaf springs affixed to the cage and engaged against ends of the at least one slip. Additionally, a biasing element, such as a spring or the like, can be engaged between the cage and the mandrel and can bias the at least one slip to the unset condition.
Similar to the operation of the anchor, the fluid passageway communicating in the mandrel with the workstring and conveying fluid can use the same or even a different valve for selectively communicating fluid conveyed through the mandrel to the at least one puller piston. Either way, the valve can include a seat disposed in the fluid passageway that is engageable by a deployed ball.
In one form of operation to retrieve a well component downhole with an implement, the well component is engaged with the implement on the pulling tool manipulated downhole with the workstring. The well component can be a stuck pipe or the like in the casing downhole, and the implement can be a fishing tool or the like.
With the implement engaged, the well component is then pulled by hydraulically moving at least one puller piston along a mandrel of the pulling tool in response to fluid pressure communicated down the workstring. The pulling tool is also anchored at a point uphole of the puller piston by hydraulically moving an anchor piston along the mandrel of the pulling tool in response to the communicated fluid pressure and wedging at least one slip outward from the mandrel with the movement of the anchor piston.
Before actually engaging the implement, however, some form of initial operations can be performed. In this case, the pulling tool can be initially manipulated downhole while at least temporarily holding the pulling tool in an unextended condition so that initial operations, such as cutting, can be performed. Eventually, the pulling tool can be released to extend to an extended condition so that the pulling operations can then be performed.
To at least temporarily holding the pulling tool in the unextended condition, a detachable coupling can be provided for the at least one puller piston to the mandrel. In an attached condition, the detachable coupling holds the at least one puller piston in the unextended condition on the mandrel, while the detachable coupling in a detached condition permits the at least one puller piston to extend on the mandrel. In one arrangement, the detachable coupling includes a collet disposed on the at least one puller piston and detachably engageable with at least one detent on the mandrel.
Another form of operation can also be used to retrieve a well component downhole with the implement on the pulling tool. As before, the well component can be engaged with the implement on the pulling tool manipulated downhole. Similarly, the well component can be pulled with the implement by hydraulically moving at least one puller piston along a mandrel of the pulling tool in response to communicated fluid pressure.
Anchoring the pulling tool at a point uphole of the puller piston can likewise use at least one slip wedged outward from the mandrel. However, in contrast to using an anchor piston to move the at least one slip, first movement of the at least one puller piston can be translated to second movement of the at least one slip for wedging in the casing. The first movement of the puller tool can permitted up to a first limit in a first direction so that over setting of the at least one slip is avoided.
In this way, the at least one slip is hydraulically actuated from the unset condition to the set condition by the at least one puller piston. To do this, the at least one slip can have a slip cage connected to the at least one puller piston. The slip cage can move on the mandrel with the movement of at least one puller piston and can force the at least one slip against a ramp surface on the mandrel.
To limit this movement, a detachable coupling can connect the slip cage to the at least one puller piston. The detachable coupling can translate first movement of the at least one puller piston up to the first limit in the first direction to second movement of the slip cage. Up to that limit then, the second movement of the slip cage can thereby wedge the at least one slip against the portion of the mandrel. Yet, the detachable coupling preferably does not translate movement of the puller piston past that limit to movement of the slip cage.
The detachable coupling can include a collet disposed on the at least one puller piston and detachably engageable with at least one detent on the slip cage. The at least one detent can use a first detent on the slip cage at least temporarily preventing passage of the collet in the first direction past the first detent. A second detent on the slip cage can prevent passage of the collet in a second opposite direction past the second detent.
To provide the desired release after operations, the detachable coupling can also translate third movement of the at least one puller piston in a second direction to fourth movement of the slip cage. This movement of the slip cage can remove the at least one slip from against the portion of the mandrel.
The foregoing summary is not intended to summarize each potential embodiment or every aspect of the present disclosure.
When a well component 15 becomes stuck downhole, operators use a retrieval assembly 20 as shown in
The retrieval assembly 20 has a pulling tool 100 according to the present disclosure. The pulling tool 100 may be used as a replacement for surface casing jack systems to retrieve stuck casing 15 or the like. In fact, the pulling tool 100 can be used to retrieve stuck casing 15 in applications where the drilling rig 30, platform, drillship, etc. or where the workstring 35 does not have sufficient capacity to pull the casing 15. Indeed, being able to remove casing 15 with the pulling tool 100 and without the need to perform milling operations can save rig time, reduce wear on rig equipment, and can eliminate swarf handling.
Operators deploy the pulling tool 100 on the workstring 35 into the wellbore from the rig 30, which has a pump system 32. Various types of implements 50 and fishing tools can be used depending on the implementation and the operation to be performed. Accordingly, the pulling tool 100 can be used with various types of implements 50, such as standard casing cutting and fishing tools. When the implement 50 is engaged with the casing 15, the pulling tool 100 is used to exert the pulling force required to retrieve the casing 15.
The pulling tool 100 has an anchor 160 and a puller 110. The anchor 160 couples to the workstring 35, and the puller 110 extends further downhole from the anchor 160. At its distal end, the pulling tool 100 has the implement 50 supported on the puller 110 for engaging the well component 15. Further details of the tool 100 with its anchor 160 and puller 110 are shown in
In a pulling operation, for example, the pulling tool 100 is run on the workstring 35 downhole to a section of stuck casing 15 to be pulled uphole. The fishing tool 50 on the end of the pulling tool 100 is then located and tagged in the end of the stuck casing 15. For example, the fishing tool 50 may be a spear, although any suitable type of tool, such as a basket grapple, spiral grapple, die collar, tapered taps, etc., can be used depending on the implementation.
The fishing tool 50 is then set to engage the stuck casing 15. With the fishing tool 50 set, the pulling tool 100 is in an unstroked condition, such as shown in cross-section in
With the fishing tool 50 set as in
The applied pressure sets the anchor 160 in the outer casing 10 and strokes the piston(s) 130 of the puller 110 to a closed position. In the stroked condition as shown in
This stoked action of the tool 100 jacks (pulls) the stuck casing 15 of
On the disclosed pulling tool 100, the anchor 160 is disposed uphole from the puller 110, which means the major pull loads are taken by the heavy body of the puller 110 and not by the smaller inner dimensions of the anchor's components. The gives operators the ability to exert larger pulling forces due to the larger cross-section of the pulling mandrel 162 resulting from this arrangement. Additionally, when manipulating the tool 100 and the workstring 35, all downhole torque is done through the larger OD members of the puller 110.
For some example details on one implementation, the implement 50 can be a spear. The workstring 35 is rotated to set the spear 50 in the stuck casing 15, which can be a section of 9⅝-in. casing stuck in 13⅜-in. casing 10. When operated, the pulling tool 100 may be capable of generating a minimum 2,000,000-lbs downhole pulling force, can be about 50-ft long, can operate with maximum pressure of about 6,700-psi, and may have a 36-in. stroke length to pull the stuck casing 15. Other implementations and variables are possible as will be appreciated by one skilled in the art.
With an understanding of the operation of the pulling tool 100, discussion now turns to particular details related to the anchor 160 and the puller 110 of the disclosed tool 100.
Looking first at the anchor 160,
The anchor 160 has an anchor mandrel 162 that can couple to the workstring (35) at an uphole end in a conventional manner and can form a part of the overall mandrel of the pulling tool (100). The anchor mandrel 162 defines a fluid passageway or bore 164 communicating with the workstring (35) and conveying fluid to various components of the tool (100) as discussed below.
The anchor 160 has an anchor piston 170 and at least one slip 180 disposed on the anchor mandrel 162. Preferably, multiple slips 180 are disposed around the circumference of the anchor mandrel 162 (See
As can be surmised, the slips 180 in the set condition can engage downhole by setting in the outer casing 10, for example. Preferably, the each slip 180 distributes the load of the pulling tool (100) along a length of the outer casing 10. In one implementation, for example, the slips 180 can be long rectangular bodies with a length of about 30-in.
As best shown in the end-sections of
The anchor piston 170 is hydraulically movable from a first condition (
In the second condition (
The slips 180 in the unset condition (
As best shown in the detailed views of
The anchor piston 170 also has at least one second biasing element 178b disposed between the anchor piston 170 and the slips 180. This second biasing element 178b can be a push spring having one portion engaged against the anchor piston 170 and having an opposing portion engaged against the slips 180 via the slip cage 182.
As also best shown in the detailed views of
The spring retainers 184a-b on each end of the slips 180 are multi-functional. The spring retainers 184a-b during operations not only hold each slip 180 in place, but they also assist in the return of the slips 180 to the reset positions. Additionally, the screws holding the spring retainers 184a-b on the split cage 180 are removable, which allows operators to easily replace slips 180 if worn or if new slips 180 are needed to accommodate a change in casing weights. This can be done on the rig floor if needed.
When internal pressure is applied, the anchor piston 170 moves up toward the slip cage 182 with the piston's force transferred to the cage 182 by the push spring 178b. Movement of the slip cage 182 forces the slips 180 out against the casing 10 by riding the slips' ramps 188 against the mandrel's ramps 168 and wedging the slips 180 against the mandrel 162. The movement of the anchor piston 170 is limited by a shoulder 165 on the mandrel 162. As can be seen, the push spring 178b allows for some play and adjustment between the components, which may be desirable during operations.
When pressure is released, the slips 180 may remain in their extended (catch) position due to the downward weight and the pull of the puller (110) and other components. The upward pull of the mandrel 162, however, relieves the wedging between the ramped surfaces 168/188 so the slips 180 can dislodge from inside of the casing 10 and release the anchor 160 to the reset position. The return spring 178a on the mandrel 162 also presses back against the anchor piston 170 (in the absence or release of pressure) to help move the piston 170 back in the reset position, which also helps place the slips 180 in their retracted (released) position as well. Finally, the other springs 184a-b and 186 can further assist with unsetting the slips 180.
Looking now at the puller 110,
The puller 110 has a puller mandrel 120 that couples at its uphole end to the anchor (160) and extends from the anchor mandrel (162). The puller mandrel 120 therefore forms part of the overall mandrel of the tool (100). At least one puller piston 130 is disposed on the puller mandrel 120 at at least one piston head 140 on the mandrel 120.
Although one puller piston 130 is shown in
The puller piston 130 is hydraulically movable relative to the puller mandrel 120 from an extended condition (
The puller mandrel 120 defines a fluid passageway or bore 122 communicating with the workstring (35) via the anchor (160). A valve 126 in the puller bore 122 can selectively communicate fluid conveyed through the puller mandrel 120 to the puller piston(s) 130 and the anchor (160). For example, the valve 126 can be a ball seat to engage a dropped ball 128 deployed to the puller 110 during operations. Other types of valves, seats, or the like could be used.
In one example, a sleeve and port arrangement can be used for the valve 126 that is activated by a Radio Frequency Identification (RFID) tag or the like, using techniques known in the art. When an appropriate RFID tag is deployed to the tool 100, for example, the valve 126 can close to selectively communicate fluid through the puller mandrel 120 to the puller piston 130. In other examples, a mechanical sleeve using j-slots and the like can be used to mechanically open and close circulation to the puller piston 130.
During operations when fluid pressure is pumped behind the closed valve 126, the hydraulic pressure actuates the puller piston(s) 130. In particular, the hydraulic pressure exits from the mandrel's bore 122 to the intermediate chamber 136 via cross-ports 142 at the piston head 140 (see
The above pulling tool 100 may be deployed and manipulated downhole while the puller 110 is in an extended condition. Closing of fluid communication through the tool 100 and the build-up of hydraulic pressure would then activate the puller 110 to its pulled condition. It may be desirable, however, to deploy and manipulate the disclosed pulling tool 100 downhole while it is in its unextended condition. Accordingly, another pulling tool 100 according to the present disclosure shown in
This pulling tool 100 is similar to that disclosed above and has the anchor 160, the puller 110, and other similar components so that the same reference numerals are used for similar components. The pulling tool 110 includes the detachable coupling 150 between the anchor 160 and the puller 110. Using the detachable coupling 150, the pulling tool 110 can be held in an unextended condition when deployed downhole so various operations can be performed with other tools on the end of the pulling tool 100.
The detachable coupling 150 is disposed at the end of the pistons 130, such as the end that rides on a torque transmission, splines, or hex drive 125 of the puller's mandrel 120. The detachable coupling 150 as shown here includes a collet 137 that engages a detent 127, ridge, circumferential shoulder, etc. on the puller's mandrel 120.
Assembled as shown in
Finally, subsequent operations of the pulling tool 100 can commence. For example,
As noted above, the disclosed pulling tool 100 with the detachable coupling 150 to hold the tool 100 unextended can be used in other operations, which may use other downhole tools. As shown in
For instance, the cutter 200 can be operated using communicated fluid and a mud motor, although other types of cutters could be used. Operators can cut casing with the cutter 200. Then, by pulling up, operators can detach the coupling 150 so that the piston 130 and mandrel 120 can be stroked to prepare for activation and pulling of the newly cut casing section.
As will be appreciated, in addition to a cutter and cutting operation, any number of other tools and operates can benefit from the detachable coupling 150 that maintains the pulling tool 100 unextended during use.
Yet another pulling tool 100 according to the present disclosure shown in
As only schematically shown here, the anchor's mandrel 162 couples to the puller's mandrel 120 to form the overall mandrel of the tool 100. An extension or sleeve 183 of the cage 182 extends from the anchor's slips 180 to the uppermost piston 130. A detachable coupling 139 connects the piston's end to the cage's sleeve 183, which has detents 187. As shown, the detachable coupling 139 includes a collet that can telescopically fit over the cage's sleeve 183 to engage and disengage relative to the sleeve's detents 187. A reverse arrangement could also be used.
During run in as shown in
Should operation of the tool 100 fail at this point for whatever reason, the small amount of play will enable operators to stop activation of the tool 100 and release the tool 100 using the slack provided by the offset in the detents 189a-b. For example, if the fishing implement (50) does not move the stuck casing as the piston 130 is first activated, the offset in the movement can allow operators to pull up on the tool 100 even after starting the stroke of the piston 130.
Nevertheless, activation of the piston 130 pushes the collet 139 against the intermediate detent 189b as shown in
Eventually, as shown in
Unsetting the pulling tool 100 involves a reverse operation. While fluid flow is ceased, operators pull up on the pulling tool 100. The anchor mandrel 162 can move relative to the slips 180 biting into the casing 10 so that the ramped surfaces 168 and 188 can unwedge. The springs 184a-b and 186 (if present) can tend to retract the unwedged slips 180. The piston's collet 139 can slide freely along the cage's sleeve 183 as the piston 130 tends to extend along the puller mandrel 120. Eventually, the collet 139 can reach the intermediate detent 189b and tend to further pull the cage 182 to unset the slips 180. Finally, the collet 139 can reach the hard detent 189a that pulls the cage 182 to its initial, unset condition. Repeat pulling operations can then be performed if necessary.
The foregoing description of preferred and other embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived of by the Applicants. As disclosed above, certain components have been disclosed as being modular in nature, which can facilitate assembly and use. This is not strictly necessary as certain components can be combined and integrated with one another to construct the disclosed tool. In this regard, the anchor mandrel and the puller mandrel need not be separately coupleable elements but may in fact be constructed as an integral mandrel component. This and other modifications will be appreciated by one skilled in the art having the benefit of the present disclosure.
It will be appreciated with the benefit of the present disclosure that features described above in accordance with any embodiment or aspect of the disclosed subject matter can be utilized, either alone or in combination, with any other described feature, in any other embodiment or aspect of the disclosed subject matter.
In exchange for disclosing the inventive concepts contained herein, the Applicants desire all patent rights afforded by the appended claims. Therefore, it is intended that the appended claims include all modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.
| Number | Date | Country | |
|---|---|---|---|
| 62049059 | Sep 2014 | US |
