GB2291449A

GB2291449A - Running and sting off tool assembly

Info

Publication number: GB2291449A
Application number: GB9514680A
Authority: GB
Inventors: David Earl Cain; Neil C Crawford; Bashir M Koleilat; John R Herold; Martin L Samuels; Donald B Wafer
Original assignee: FMC Corp
Current assignee: FMC Corp
Priority date: 1994-07-19
Filing date: 1995-07-18
Publication date: 1996-01-24
Also published as: GB9514680D0

Abstract

The assembly comprises a tool body 11 having an end adapted to engage a well mechanism (e.g. valve stinger 52, Fig. 6) for manipulation thereof; an indicator sleeve 13 telescopically received around said tool body 22, said sleeve and tool body being adapted to move along an axial direction relative to each other when said tool body manipulates said mechanism. Resilient retaining means 15 (e.g. a garter spring) co-operates with one or the other of a pair of detents (e.g. annular grooves 30, 32) when the indicator sleeve 13 is in its upper (not shown) or lower (as shown) positions respectively. A protector sleeve 12 carried by the tool body 11 surrounds the indicator sleeve 13. <IMAGE>

Description

RUNNING AND STING OFF TOOL ASSEMBLY The present invention relates to running tools used in oil or gas wells and, more particularly, to a tool assembly for running and stinging off of back pressure valves and tree test plugs.

In well operations, tools are used for running, or setting in place, of back pressure valves or tree test plugs and stinging off, or releasing pressure trapped underneath of, such valves or plugs. Back pressure valves are one-way valves set in a tubing hanger for retaining pressure in the well. Tree test plugs are back pressure valves used in christmas tree assemblies.

Known running and sting off assemblies are provided with means for indicating if a back pressure valve or tree test plug has been tested properly. Such indication means have comprised, for example, one or more mechanical pins housed in a surrounding shroud which are moved from a pre-test position to a post-test position. The pins are housed separately from the stem and collar of the tool. These types of assemblies, however, are subject to failure due to, for example, stem weakness. When the stem is weak such that deformation occurs causing undesired relative displacement between the stem and the indication means, the result is lack of reliability of the indication means. It is therefore an object of the present invention to provide a reliable, durable multi-function running and sting off device having indication means.

In accordance with the present invention, there is provided a running and sting off tool assembly for manipulating a mechanism in a well, comprising: a tool body having an end adapted to engage the mechanism for manipulation thereof; and an indicator sleeve telescopically received around the tool body for axial movement relative thereto when the tool body manipulates the mechanism.

Further preferred features of the invention are in the dependent claims, or will be apparent from the following description of illustrative embodiments, made with reference to the drawings, in which: Fig. 1 is a sectional view of a prior art running and sting off assembly; Fig. 2 is a partial, sectional view of a running and sting off assembly forming a first embodiment of the invention; Fig. 3 is a sectional view of the tool body of the assembly of Fig. 2; Fig. 4 is a sectional view of the protector sleeve of the assembly of Fig. 2; Fig. 5 is a sectional view of the indicator sleeve of the assembly of Fig. 2; Fig. 6 is a sectional view of an assembly similar to Fig. 2 in use with a back pressure valve, in which the indicator sleeve is in the down position; Fig. 7 is an exploded view of Fig. 6; and Fig. 8 is a sectional view of the assembly of Fig. 6 in use with a back pressure valve, in which the indicator sleeve is in the up position.

A prior art running and sting off assembly is illustrated in Fig. 1. The assembly comprises a tool stem 1 and a tool collar 3, housed and supported in an annular shroud 2 for positioning over a well assembly in order to perform running or sting off operations. The shroud 2 is fitted over the well assembly and the stem 1 and collar 3 are rotatably received in the shroud 2 for manipulating various mechanisms. A shear pin 5 is provided at the end of the collar 3 for connection to a mechanism to be manipulated, such as a stinger. Indicating means such as a pin 4 are provided for indicating whether or not a plug or valve has been set or whether or not a stinger body has been manipulated. The indicating pin 4 is adapted to displace upon physical contact with one or more components to indicate completion of the operation being carried out.In the prior art embodiment of Fig. 1, the indicator pin 4 is housed at a radially distant location from the tool stem 1.

The embodiment of a running and sting off assembly illustrated in Fig. 2, comprises a tool body 11, an annular protector sleeve 12, an indicator sleeve 13, an 0ring 14, a garter spring 15, and a roll pin 16. The tool body 11, illustrated in Fig. 3, has a generally cylindrical shape having a first end 17, a central portion 18, and a second end 20 having a nose 22 with a bevelled end opening 26 with a bevelled outer edge 24. The nose 22 has a central inner edge 28. The central portion 18 has a greater diameter than the first and second ends 17, 20 and has at least a first 30 and a second 32 annular groove.

The protector sleeve 12 is illustrated in Fig. 4. The sleeve 12 is a generally tube shaped member having a first end 34 adapted to fit snugly around the central portion 18 of the tool body 11. The first end 34 abuts 0-ring 14 which is received in a groove 36 on the body 11. The sleeve 12 has an enlarged inner diameter section 38 to provide clearance for relative reciprocation of the indicator sleeve 13 which is received telescopically inside the protector sleeve 12 and around the tool body 11.

The indicator sleeve 13 is illustrated in Fig. 5. The indicator sleeve is generally ring-shaped and comprises an internal annular groove 40 adapted to receive the garter spring 15. The garter spring 15 retains the indicator sleeve 13 on the tool body 11 in the up or down position.

The garter spring 15 is received in the second groove 32 or the first groove 30 when the indicator sleeve 13 is in the down or up position, respectively.

A running and sting off assembly 44 embodying the invention and operating in identical manner in all material respects to the embodiment of Figs. 2-5 is illustrated with reference to Figs. 6 to 8. Prior to setting a back pressure valve, the assembly 44 is positioned over a back pressure valve assembly 42 as shown in Fig. 6. The valve assembly 42 comprises a mandrel 46 received in a cap 48 positioned over a valve body 50 receiving therein a stinger 52. The tool body 11 is connected to the stinger 52 by receiving the stinger 52 in the central end opening 26. The indicator sleeve 13, is shown in the down position, wherein garter spring 15, retaining the sleeve 13, is in the second groove 32.

During stinging off, as illustrated in Fig. 6, and setting of the valve 42, as shown in Fig. 8, the tool assembly 44, the mandrel 46 and stinger 52 are moved vertically downward with respect to the remainder of the valve assembly 42, moving the indicator sleeve 13 until it contacts the valve cap 48. Movement of the rest of the tool, the mandrel and the stinger continues until the lower surface of the central portion 18 of the tool body 11 contacts the valve cap 48 as shown in Fig. 8. This causes the indicator sleeve 13 to move vertically upward relative to the tool body 11 until the garter spring 15 is received in the first groove 30. This relative movement of the indicator sleeve 13 is detected and setting or stinging off is indicated.

Although preferred embodiments of the invention have been herein shown and described, it is contemplated that variation and modification of the preferred embodiment can be made without departing from what is regarded as the scope of the present invention, as defined in the claims.

Claims

CLAIMS:

1. A running and sting off tool assembly for manipulating a mechanism in a well, comprising: a tool body having an end adapted to engage the mechanism for manipulation thereof; and an indicator sleeve telescopically received around the tool body for axial movement relative thereto when the tool body manipulates the mechanism.

2. An assembly as claimed in claim 1 wherein the indicator sleeve is retained on the tool body by resilient retaining means adapted to be selectively positioned in either one or the other of first and second detents defined between the tool body and the sleeve, the retaining means being positioned in the first detent when the indicator sleeve is in an up position and being positioned in the second detent when the indicator sleeve is in a down position.

3. An assembly as claimed in claim 2 wherein the first and second detents comprise grooves defined between the tool body and the sleeve, and the retaining means comprise a ringshaped element adapted to co-operate selectively with the first and second grooves in the up and down positions of the sleeve respectively.

4. An assembly as claimed in claim 3 wherein the first and second grooves are formed annularly about the tool body.

5. An assembly as claimed in any of claims 2-4 wherein the retaining means comprise a spring.

6. An assembly as claimed in any preceding claim comprising a protector sleeve carried by the tool body and surrounding the indicator sleeve.

7. An assembly as claimed in any preceding claim wherein the end of the tool has a central opening for receiving and manipulating the mechanism in use.

8. A running and sting off tool assembly substantially as described with reference to or as shown in Figs. 2-8 of the drawings.