GB2295631A

GB2295631A - Hydraulically actuated running tool

Info

Publication number: GB2295631A
Application number: GB9424478A
Authority: GB
Inventors: Mark Buyers; Simon Benedict Fraser; Glenn Weldan Holcombe
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-12-03
Filing date: 1994-12-03
Publication date: 1996-06-05
Anticipated expiration: 2014-12-03
Also published as: GB9424478D0; GB2295631B

Abstract

A hydraulically actuated running tool (21) is disclosed for conveying and setting 2 downhole tool (20) at a remote location in a borehole. The running tool (21) comprises a latch (4, 23) adapted to grip the downhole tool (20), a piston (7) moveable from a first position in which the latch (4, 23) is locked, to a second position in which the downhole tool (20) is released from the latch (4, 23), and a valve for controlling the movement of the piston (7) when a predetermined pressure level is reached. <IMAGE>

Description

HYDRAULIC WIRELINE TOOL This invention relates to a hydraulic wireline tool and which is particularly, though not exclusively, suitable for conveying and setting a downhole tool at a remote location in a borehole.

The wireline tool of the invention is suitable for use during the extraction or production of oil, gas or water from an underground source.

During the extraction of oil or gas from underground reservoirs or deposits, various tools or devices need to be installed in the well or borehole. Each tool is designed to perform a specific task; for example measure well parameters, clear a blockage in the borehole, extract a stuck tool or to seal the well. These tools are often attached to a device known as a lock mandrel which has one or more surfaces adapted to mate with a nipple or engagement profile of the equipment installed in the well.

A known technique of installing a lock mandrel involves attaching the lock mandrel to a running tool which controls the actuation of the mandrel. The mandrel and running tool are lowered into the well until they reach the required depth. The lock mandrel is set in position by an upward and downward movement to hammer or jar the lock mandrel into its profile.

This upward and downward mechanical movement also disengages the running tool from the mandrel once the mandrel is locked in position. The running tool can then be withdrawn from the borehole.

Mechanical actuation of the lock mandrel is not efficient and operators sometimes experience difficulty in securing the lock mandrel in position. Furthermore, drilling techniques have been developed which extract oil or gas via boreholes with high angles of deviation. Mechanical actuation in these wells is particularly difficult and sufficient force from jarring or hammering may not be available to secure the lock mandrel in position. Therefore, there is a need to develop a wireline tool for conveying and setting a downhole tool effectively in boreholes, and particularly boreholes with high angles of deviation.

According to one aspect of the invention there is provided a wireline tool for conveying and setting a downhole tool at a remote location in a borehole and which comprises: a latch adapted to grip a downhole tool; actuator means movable from a first position in which the latch is locked, to a second position in which a downhole tool is released from the latch; and a valve for controlling the movement of the actuator from the first position to the second position at a predetermined pressure value.

The wireline tool of the invention has the advantage that it does not require upward or downward mechanical movement to set a downhole tool. Instead a downhole tool can be set in position by a hydraulic technique involving an increase in fluid pressure in the borehole in order to release the latch and set the downhole tool. The wireline tool can be used effectively in boreholes with high angles of deviation and reduces down time associated with using mechanical techniques, such as jarring or hammering to activate a tool.

Preferably, the actuator means comprises an annular piston slidable on a piston shaft; said annular piston, piston shaft and latch means being substantially concentric. In its first position the piston impinges directly on the latch to ensure that a downhole tool is locked to the wireline tool for lowering into a borehole.

The latch may comprise a body and a plurality of flexible fingers extending from the body; the ends of said fingers being adapted to grip a downhole tool in use.

Barbs may be provided at the end of each of the fingers. The barbs locate in a recess in a downhole tool and prevent the tool being released until the wireline tool is activated.

Preferably, the valve comprises a valve piston slidable within a cylinder from a first open position in which fluid flow through the valve is permitted, to a second position in which fluid flow is prevented; and a spring arranged to urge the piston towards the second position at a predetermined pressure.

The valve determines when the wireline tool releases and sets the downhole tool. In use, the tools are lowered into a borehole to a location at which the downhole tool is to be released and set. At this depth an operator increases the pressure by pumping at the surface. At the predetermined pressure value the valve permits fluid to flow through the tool and allows the annular piston to move to its second position thereby releasing the latch and the downhole tool.

Preferably, the valve is adjustable. An adjustable valve allows an operator to select a predetermined pressure value at which the valve will operate. Adjustment may be achieved by altering the force exerted on the piston by the spring.

According to a second aspect of the invention there is provided a method of installing a downhole tool at a remote location in a borehole which comprises: connecting a downhole tool to a hydraulic wireline tool; lowering said downhole tool and wireline tool into a borehole to a remote location; and increasing fluid pressure to a predetermined pressure to activate the wireline tool and release and set the downhole tool; in which the wireline tool includes a latch adapted to grip the downhole tool; actuator means movable from a first position in which the latch is locked, to a second position in which a downhole tool can be released from the latch; and a valve for controlling the movement of the actuator from the first position to the second position at a predetermined pressure value.

According to a further aspect of the invention there is provided a mandrel lock which comprises: a cylindrical housing; a latch which grips the end of a sleeve, said sleeve being slidable within said housing from a first position in which the tool can be run into a borehole, to a second position in which the tool is set and prevented from moving; actuator means for preventing the sleeve from being released in its first position, and a valve for controlling movement of the actuator and the sleeve to its second position at a predetermined pressure.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional side view of a hydraulic wireline tool according to the invention; Figure 2 is a cross-sectional side view of a wireline tool and downhole tool connected together and ready for running into a borehole; Figure 3 is a cross-sectional side view of the tools shown in Figure 2 with the wireline tool activated and the downhole tool set in position; and, Figure 4 is a cross-sectional side view of a downhole tool in position and set, the wireline tool having been detached and withdrawn from the downhole tool.

Referring to the drawings in detail, Figure 1 shows a hydraulic wireline tool according to the invention, generally indicated by reference numeral 1, which comprises a body 2, and a latch 3 secured to the body 2 and adapted to grip a downhole tool in use. A plurality of fingers 4 extend downwardly from the latch body 5. Barbed portions 6 at the end of each of the fingers are adapted to grip an internal surface of a downhole tool as it is conveyed into the borehole. An annular piston 7 slidable on a piston shaft portion 8 of the body 2, said piston being slidable from a first position (as shown in Figure 1) in which the fingers 4 of the latch 3 are prevented from moving inwards towards the shaft 8, to a second position in which the fingers are detached from a downhole tool so that it can be released from the latch 3.A valve 9 controls movement of the piston 7 from its first position to its second position at a predetermined pressure value. The valve comprises a valve piston 10 slidable within a cylinder 11. A spring 12 urges the piston 10 upwards to close the flow ports 13. To operate the wireline tool 1, to release a downhole tool, the pressure of fluid in the flow passages 14 is increased by pumping at the surface. At a predetermined pressure the piston 10 opens the flow ports 13 and fluid can drain from the passages 14 and the annular chamber 15 through the piston 10 via passage 16 and then through flow passages 17 and 18 to the lower end of the tool where the pressure is lower ie. a pressure differential exists. As fluid drains from the annular chamber 15, the piston 7 moves from its first position towards its second position.The fingers 4 can move inwards thereby allowing the downhole tool to be released. The predetermined pressure value at which the valve operates can be selected by an operator according to the operating conditions. This can be achieved by adjusting the pressure which the spring 12 exerts on the piston 10.

Figure 2 shows a downhole tool 20 connected to the wireline tool 21 according to the invention. Although the downhole tool in this figure is a lock mandrel, it must be appreciated that the wireline tool of the invention is not exclusively limited to this type of tool and that other tools which require actuation at a remote location in a borehole can be used with the invention. The wireline tool 21 and the downhole tool 20 are locked together. The barbed portions 6 of the fingers 4 are sandwiched between the external surface of the piston 7 and the internal surface of the sleeve 22. Protrusions 23 on the sleeve 22 and the barbed portions 6 prevent the tools from being separated. In this configuration the annular chamber 15 is filled with fluid and the piston 7 is in its first position.

The tools can be lowered into a borehole to a remote location where the downhole tool is to be released. Locking members 24 are in their retracted positions so that the tool can move freely within the borehole.

Once the downhole tool has been positioned at the desired depth in the borehole, the wireline tool can be hydraulically operated to release and set the downhole tool. To achieve this, an operator at the surface increases the fluid pressure to a predetermined level, at which pressure the piston 7 moves down to its second position (as shown in Figure 3). An example of a predetermined pressure level would be about 400 psi. The fingers 4 are released and on travelling towards the second position the piston 7 impinges on the shoulders 30 of the sleeve 22 causing the sleeve to move downwards relative to the housing 31 of the downhole tool 20. As the sleeve 22 moves downwards sleeve members 32 force locking members outwards thereby locking the downhole tool in position. Once the piston 7 has reached its second position the pressure applied at the surface can be bled off. The wireline tool 21 can now be withdrawn from the downhole tool 20. As the wireline tool is withdrawn, shoulder 33 on body 2 abuts against sealing sleeve 34 causing the sleeve to move upwards and seal ports 35. This closes communication to the lower pressure differential and creates a pressure tight seal across the downhole tool. The sealing sleeve 34 is prevented from returning to the open position by the abutment between sleeve portions 36 and shoulders 37.

Claims

CLAIMS:

1. A wireline tool for conveying and setting a downhole tool at a remote location in a borehole and which comprises: a latch adapted to grip a downhole tool; actuator means movable from a first position in which the latch is locked, to a second position in which a downhole tool is released from the latch; and a valve for controlling the movement of the actuator from the first position to the second position at a predetermined pressure value.

2. A wireline tool according to Claim 1, wherein the actuator means comprises an annular piston slidable on a piston shaft; said annular piston, piston shaft and latch means being substantially concentric.

3. A wireline tool according to Claim 1 or 2, wherein the latch comprises a body and plurality of flexible fingers extending from the body; the ends of said fingers being adapted to grip a downhole tool in use.

4. A wireline tool according to Claim 3, further comprising barbs provided at the end of each of the fingers.

5. A wireline tool according to any one of the preceding Claims, wherein the valve comprises a valve piston slidable within a cylinder from a first open position in which fluid flow through the valve is permitted, to a second position in which fluid flow is prevented; and a spring arranged to urge the piston towards the second position at a predetermined pressure.

6. A wireline tool according to any one of the preceding Claims, wherein the valve is adjustable.

7. A wireline tool according to Claim 6, wherein adjustment is achieved by altering the force exerted on the piston by the spring.

8. A method of installing a downhole tool at a remote location in a borehole which comprises: connecting a downhole tool to an hydraulic wireline tool; lowering said downhole tool and wireline tool into a borehole to a remote location; and increasing fluid pressure to a predetermined pressure to activate the wireline tool and release and set the downhole tool; in which the wireline tool includes a latch adapted to grip the downhole tool; actuator means movable from a first tool; in which the wireline tool includes a latch adapted to grip the downhole tool; actuator means movable from a first position in which the latch is locked, to a second position in which a downhole tool can be released from the latch; and a valve for controlling the movement of the actuator from the first position to the second position at a predetermined pressure value.

9. A mandrel lock which comprises: a cylindrical housing; a latch which grips the end of a sleeve, said sleeve being slidable within said housing from a first position in which the tool can be run into a borehole, to a second position in which the tool is set and prevented from moving; actuator means for preventing the sleeve from being released in its first position, and a valve for controlling movement of the actuator and the sleeve to its second position at a predetermined pressure.

10. A wireline tool substantially as hereinbefore described with reference to the accompanying drawings.

11. A method of installing a downhole tool at a remote location in a borehole, the method substantially as hereinbefore described with reference to the accompanying drawings.

12. A mandrel lock substantially as hereinbefore described with reference to the accompanying drawings.