Claims
- 1. An apparatus for cutting and retrieving a casing string, and adapted to be utilized on a workstring, comprising:
- a hydraulically actuable grapple assembly adapted to be insertable into said casing, said grapple assembly including a plurality of slips adapted to move between a first position wherein said slips to not substantially engage said casing and a second position in which said slips substantially engage said casing, said slips moveable between said first and second positions at virtually any location within said casing, said slips movable from said first position to said second position in response to fluid pressure, said slips oriented to engage said casing and to place said casing in tension proximate the location at which said casing is to be cut;
- a mandrel assembly extending through said grapple assembly, said mandrel assembly being mounted in rotatable relation relative to said grapple assembly; and
- a cutting assembly operatively coupled to said mandrel assembly.
- 2. The apparatus of claim 1, wherein said plurality of slips include a plurality of generally circumferentially arranged segments.
- 3. The apparatus of claim 1, wherein said cutting assembly includes a plurality of radially extendable cutting elements, said cutting elements extendable in response to hydraulic pressure.
- 4. The apparatus of claim 3, wherein said slips are moveable between said first and second positions in response to fluid pressure within said workstring.
- 5. The apparatus of claim 2, wherein said generally circumferentially disposed segments are supported about said periphery by a support, which support includes an upwardly tapering truncated cone generally coaxially arranged with said mandrel.
- 6. The apparatus of claim 5, wherein said truncated cone of said support defines at least one tapered angle in the range of approximately 4.degree.-30.degree..
- 7. The apparatus of claim 2, wherein said generally circumferentially disposed segments include a plurality of teeth disposed about their outer contacting surfaces, said teeth having tangential cut angles when viewed in end cross section and axial cut angles when viewed in side cross section.
- 8. The apparatus of claim 1, further comprising a spring assembly operatively associated with said slips, said spring assembly operable to urge said slips from said second position toward said first position when said hydraulic pressure is reduced.
- 9. An apparatus adapted for use with a workstring to cut and remove casing from a well, said apparatus adapted to allow multiple cuts of said casing on a single trip of the workstring into said well, comprising:
- a spear assembly having a connector to facilitate coupling of said assembly to said workstring, said spear assembly comprising,
- a mandrel,
- a housing assembly rotatably mounted around said mandrel, and a plurality of grapple slips generally circumferentially arranged around said body assembly, said slips moveable between a first position and a second position, wherein in said second position said slips will engage said casing and allow tension to be applied to said casing through said workstring, and wherein in said first position said slips will substantially be disengaged from said casing and allow movement of said spear assembly upwardly and downwardly through said casing said slips from said first position to said second position in response to fluid pressure; and
- a cutting assembly coupled to said mandrel and adapted to selectively cut said casing.
- 10. The apparatus of claim 9, wherein said plurality of grapple slips are moveable between said first and second positions in response to fluid pressure within said workstring.
- 11. The apparatus of claim 9, wherein said body assembly includes a grapple support member having at least one generally conical support section operatively engaging generally inner surfaces of said grapple slips, wherein movement of said grapple slips relative to said conical support section causes movement of said grapple slips between said first and second positions.
- 12. The apparatus of claim 9, wherein said plurality of grapple slips include teeth which are adapted to grip the inner diameter of said casing when said slips are in said second position and to minimize both axial and rotational movement between said body assembly and said casing.
- 13. The apparatus of claim 9, further comprising a spring operatively associated with said slips, wherein said slips are moveable from said second position to said first position at least partially in response to a force applied by said spring.
- 14. A method for cutting and removing casing from a wellbore on a single trip of a workstring into said wellbore, comprising the steps of:
- securing a cutting assembly and a grapple assembly to said workstring, said cutting assembly being selectively actuable at least partially in response to hydraulic pressure and said grapple assembly being actuable at least partially in response to hydraulic pressure;
- lowering said cutting assembly and said grapple assembly into said wellbore until said cutting assembly is at a depth where it is desired to cut said casing;
- applying hydraulic pressure in said workstring to actuate said grapple to cause said grapple to engage said casing;
- applying tension to said workstring to place said casing in tension through said grapple assembly;
- rotating said workstring to rotate said cutting assembly, which has been extended in response to hydraulic pressure, so as to cut said casing; and
- after said casing has been cut, applying pull on said workstring to remove said casing from said wellbore.
- 15. The method of claim 14, further comprising the steps of:
- releasing said hydraulic pressure to release said grapple assembly from engagement with said casing;
- moving said workstring to place said grapple assembly at a different desired placement within said cut casing section; and
- applying hydraulic pressure to cause said grapple assembly to engage said casing at said different desired location in said casing.
- 16. The method of claim 14, further comprising the steps of:
- attaching a drilling jar to the workstring; and
- after cutting said casing, actuating said drilling jar to impart an impact force on said casing.
Parent Case Info
This application is a continuation of application Ser. No. 824,863, filed Jan. 22, 1992, now abandoned, which is a continuation of Ser. No. 672,089, filed Mar. 19, 1991, now abandoned.
US Referenced Citations (8)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0155129 |
Sep 1985 |
EPX |
2194978 |
Mar 1988 |
GBX |
Non-Patent Literature Citations (5)
Entry |
Publication by The Red Baron (Oil Tools Rental), entitled The Red Baron-Sales and Service Catalogue, pp. 12-15, dated "1990-91", published in the 1990-91 Composite Catalog. |
Publication of Houston Engineers, Inc., entitled "Universal Rotating and Releasing Spear," p. 14, published 1983. |
Catalogue of A-Z International Tool Co., entitled "A-Z Hydraulic Spear" pp. 183 and 184, published 1976-77. |
A-Z International Tool Co., entitled "A-Z One Trip Cut and Recover Method," p. 192, published 1976-77. |
A-Z Grant General Catalog 1990-91, pp. 120-8, 120-9, published in the 1990-91 Composite Catalog. |
Continuations (2)
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Number |
Date |
Country |
Parent |
824863 |
Jan 1992 |
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Parent |
672089 |
Mar 1991 |
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