GB2461311A

GB2461311A - Cleaning tool with a downhole drive

Info

Publication number: GB2461311A
Application number: GB0811822A
Authority: GB
Inventors: Edward Docherty Scott
Original assignee: Futuretec Ltd
Current assignee: Deep Casing Tools Ltd
Priority date: 2008-06-27
Filing date: 2008-06-27
Publication date: 2009-12-30
Anticipated expiration: 2028-06-27
Also published as: GB2461311B; GB0811822D0

Abstract

A downhole cleaning tool 10 comprises a tubular body 16 and a cleaning member 22. The cleaning member 22 has a head portion 24 and shaft portion 26, the shaft portion 26 located within the body 16. The body 16 defines a stator and the shaft portion 26 defines a rotor, the body 16 and shaft portion 26 together forming a rotary drive arrangement 32 for rotating the head portion 24 relative to the body 16. The tool is adapted for location in a tubular component, such as cemented casing 12, and is adapted to facilitate cleaning of the casing 12 and/or conditioning the bore 14 of the casing 12. The cleaning member 22 may also include a number of ports and jets for the expulsion of fluid to assist in cleaning the casing 12.

Description

DOWNHOLE CLEANING TOOL

FIELD OF THE INVENTION

This invention relates to a downhole cleaning tool and, in particular, but not exclusively, to a cleaning tool for use in cleaning a downhole tubular component.

BACKGROUND TO THE INVENTION

In order to access subsurface formations, including for example hydrocarbon-bearing or geothermal formations, a bore is typically drilled from surface to a first depth and a first tubular section or string of tubular sections, known as casing, is run into the bore. The casing is suspended from surface and the annulus between the exterior of the casing and the surrounding bore wall is filled and sealed with cement.

The bore is extended and a further tubular section or string of tubular sections, known as liners, are run into the bore and suspended from the casing. The annulus between the exterior of the liner and the surrounding bore wall is also filled and sealed with cement. In order to access the formation, the liner and cement are perforated to provide a fluid flow path between the formation and the surface. * *.

Following the formation of the cemented bore, the casing and/or the liner * SI* typically comprise obstructions, including for example regions of set cement that can **** block, or otherwise obstruct, the bore of the casing and/or liner. It is therefore I..

desirable to clean the bore of the casing and/or the liner to facilitate running in or ** **.* retrievaj of tools through the casing or liner.

*****.

Furthermore, an operator may also wish to condition the bore of the casing to facilitate pressure integrity testing and the like.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided a downhole cleaning tool for location in a tubular component to be cleaned, the tool comprising: a body; a cleaning member operatively coupled to the body; and a rotary drive arrangement adapted to be located downhole, the drive arrangement adapted to rotate the cleaning member relative to the body to permit cleaning of the tubular component.

The body may be adapted to be coupied to a tubular string, such as a running string, drill string or the like, and the tool may be run into the tubular component, such as casing, with the tubular string. The Cleaning member may be adapted for relative rotation with respect to the string to facilitate cleaning of the tubular component. In particular embodiments, the tool may be run into the tubular component substantially without rotation, or with relatively low speed rotation of the string, and the cleaning member may be adapted for relatively high speed rotation relative to the body and the string to facilitate cleaning of the tubular component The cleaning member may *:*::* be adapted for rotation at a speed which may otherwise damage the string, couplings and the like.

* , 20 The cleaning member may be provided at the distal end of the body to * facilitate cleaning of the whole length of the tubular component and, in particular, but not exclusively, to permit cleaning the tubular component to total depth (TD).

I. IS** * * The rotary drive arrangement may be of any suitable form. For example, the rotary drive arrangement may comprise at least one of a fluid turbine, axial vane hydraulic motor, a positive displacement motor, an Archimedes screw arrangement, an electric motor or any other suitable rotary drive. The use of a fluid turbine may facilitate low vibration operation and may permit the power output from the rotary drive arrangement to be configured and/or reconfigured as required.

In particular embodiments, the body may define, or provide mounting for, a stator of the rotary drive arrangement. The cleaning member may be coupled to a rotor shaft and the rotor shaft may be adapted for rotation relative to the body to rotate the cleaning member. The cleaning member and rotor shaft may comprise separate components adapted for coupling together. Beneficially, the provision of a separate rotor shaft and cleaning member facilitates the use of a range of demountable cleaning members, each configured for a selected cleaning operation.

Alternatively, the rotor may be formed with the cleaning member.

The rotor shaft may be operatively coupled to the body on at least one bearing. For example, the bearing may comprise at least one of a radial bearing and a thrust bearing, though any bearing may be used where appropriate.

The rotary drive arrangement may be constructed from any suitable material.

For example, the rotary drive arrangement may be constructed from at least one of, or a combination of, a metallic material such as aluminium, aluminium alloy, steel, ceramic material, laminate material such as carbon fibre or glass fibre and * elastomeric material. For example, the rotary drive arrarigenient may comprise a e.

0S** positive displacement motor comprising a metallic rotor and an elastomeric stator.

*:. 20 The cleaning member may comprise at least one cleaning element arranged * to engage the tubular component to facilitate cleaning of the tubular component. The cleaning element may be of any suitable form and construction and may, for example, comprise at least one of a brush element, scraper element and the like. In particular embodiments, the cleaning element may comprise a scraping element constructed from a material such as phosphor bronze, whereby the scraper has sufficient rigidity and hardness to effect cleaning of the tubular component without causing damage to the tubular component. Accordingly, the cleaning element may be arranged to burnish or polish the interior surface of the tubular component.

The cleaning member may comprise or define a fluid conduit for permitting fluid through the cleaning member. For example, the cleaning member may comprise at least one port for directing fluid from the tool, thereby assisting in the cleaning of the tubular component. In particular embodiments, the port may comprise a nozzle adapted to direct fluid from the tool to further assist in cleaning the tubular component by jetting.

At least part of the tool may be adapted to facilitate drilling through the tool.

For example, at least part of the tool may be constructed from a readily drillable material which may be frangible or otherwise adapted to break. In particular embodiments, at least part of the tool may be constructed from at least one of aluminium, aluminium alloy, lead, brass, other suitable metallic material; a ceramic material; a polymeric material; a laminate material; carbon fibre; and a glass material, though any other suitable material may be used. Alternatively, or in addition, the tool may further comprise selected portions or regions of weakness. The weaker portions or regions may be cast into the tool during manufacture, for example, to produce harder and weaker portions or regions. The provision of harder portions or regions * *IS may facilitate cutting or reaming of the bore. The provision of selected weaker portions or regions may facilitate drilling through the tool, where required.

** According to a second aspect of the present invention there is provided a method of cleaning a tubular component, the method comprising: locating a cleaning tool comprising a cleaning element coupled to a distal end of a body in a tubular component to be cleaned; and rotating the cleaning element to permit cleaning of the tubular component.

Fluid, such as drilling mud or other fluid, may be directed through the tool to drive rotation of the cleaning member relative to the body to facilitate cleaning of the tubular component. The fluid may then be directed through the at least one port to assist in cleaning the tubular component.

The tool may be adapted to clean the bore of the tubular component top-down. Alternatively, the tool may be adapted to clean the bore of the tubular component bottom-up. The tool may be adapted for reciprocal movement within the tubular component.

BRIEF DESCRIPTION OF THE DRAWING

These and other aspects of the present invention will now be described, by way of example, with reference to the accompanying drawing, in which: Figure 1 is a partial longitudinal sectional view of a cleaning tool according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTiON

Referring to Figure 1, there is shown a partial longitudinal sectional view of a *..... cleaning tool 10 according to an embodiment of the present invention. The tool 10 is *.S.

adapted for location in a tubular component, such as cemented casing 12, and is *: 20 adapted to facilitate cleaning of the casing 12 and/or conditioning the bore 14 of the casing 12 to facilitate pressure integrity testing and the like.

As shown in the figure, the tool 10 comprises a tubular body 16 which is coupled to a distal end of a drill string 0 by a connector sub C. The body 16 and connector sub C are coupled together by locking nuts 18. The driU string 0, connector sub C and body 16 define a bore 20 for permitting transfer of fluid into the tool 10.

The tool 10 further comprises a cleaning member 22 having a head portion 24 and a shaft portion 26 located within the bore 20 of the body 16. The shaft portion 26 is mounted within the bore 20 of the body 16 on radial bearings 28 (three radial bearings 28 are shown in Figure 1). The tool 10 further comprises a thrust bearing 30 for restraining axial movement of the shaft portion 26 relative to the body 16.

The body 16 defines a stator and the shaft portion 26 defines a rotor and the body 16 and shaft portion 26 together form a rotary drive arrangement 32 for rotating the head portion 24 to facilitate cleaning of the casing 12.

The cleaning member 22 comprises cleaning elements in the form of brushes 34 which are adapted to engage the bore 14 of the casing 12 to facHitate cleaning.

The cleaning member 22 also comprises cleaning elements in the form of scrapers 36 which permit a more aggressive cleaning operation to be undertaken.

The scrapers 36 are constructed from phosphor bronze, which is softer than the material, typically steel, of the casing 12. This substantially prevents damage to the casing 12 by the cleaning member 22.

The cleaning member 22 comprises a fluid conduit in the form of nozzles 38 for permitting fluid through the cleaning member 22 to assist in cleaning the casing 12 by jetting, as will be described below. *...

The tool 10 further comprises a stabiliser 39 located around the body 16 and, in the embodiment shown in Figure 1, the stabiliser 39 is threadedly connected to the body 16 adjacent to the head portion 24 of the cleaning member 22.

In use, fluid in the form of drilling mud or the like is directed through the bore as shown by arrow 40 and into an annular region 42 between the body 16 and the shaft portion 26 of the cleaning member 20. The mud drives rotation of the rotor relative to the stator, thereby rotating the head portion 24 of the cleaning member 22 about an axis 44. The provision of an independently rotatable rotor permits higher speed rotation of the cleaning member 22 relative to the string D. The mud is then directed to the head portion 24 where it exits through the nozzles 38 to assist in cleaning the casing 12. In the embodiment shown, the mud is then re-circulated via an annulus 46 between the tool 10 and the casing 12.

It should be understood that the embodiment described is merely exemplary of the present invention and that various modifications may be made without departing from the scope of the invention.

For example, the rotor and stator may take the form of a positive displacement rotor and stator. In a similar fashion to the embodiment shown in Figure 1, fluid is directed between the rotor and the stator of the pdm to drive rotation of the cleaning member.

The tool may be adapted to be recovered from the bore or alternatively, the tool may be left in the bore. For example, the tool may be removed from the bore and used in another bore. Alternatively, the tool may be removed, and redressed with another or different cleaning member or cleaning element and run into the bore.

In alternative arrangements, the tool may be left in the bore, at least part of the tool * ** **** adapted for drilling through the tool. * . * * S ** *

S S..

*.**,S * *

S * S

Claims

CLAIMS1. A downhole cleaning tool for location in a tubular component to be cleaned, the tool comprising: a body; a cleaning member operatively coupled to the body; and a rotary drive arrangement adapted to be located downhole, the drive arrangement adapted to rotate the cleaning member relative to the body to permit cleaning of the tubular component.
2. The cleaning tool of claim 1, wherein the cleaning member is provided at a distal end of the body.
3. The cleaning tool of claim 1 or 2, wherein the rotary drive arrangement comprises at least one of a fluid turbine; an axial vane hydraulic motor; a positive displacement motor; an Archimedes screw arrangement; and an electric motor. * ** * * * * ** * ***
4. The cleaning tool of any one of claims 1, 2 or 3, wherein the tool comprises a conduit for directing fluid through the rotary drive arrangement. * ***
5. The cleaning tool of any preceding claim, wherein the body defines a stator of the rotary drive arrangement.
6. The cleaning tool of any preceding claim, wherein the body provides mounting for a stator of the rotary drive arrangement.
7. The cleaning tool of any preceding claim, wherein the cleaning member is coupled to a rotor shaft of the rotary drive arrangement.
8. The cleaning tool of claim 7, wherein the rotor shaft is adapted for rotation relative to the body to rotate the cleaning member.
9. The cleaning tool of any preceding claim, wherein the tool comprises a plurality of demountable cleaning members.
10. The cleaning tool of any preceding claim, wherein the cleaning member comprises at least one cleaning element arranged to engage the tubular component.
11. The cleaning tool of claim 10, wherein the cleaning element comprises at least one of a brush element; a scraper element; a polishing element; and a burnishing element.
12. The cleaning tool of any preceding claim, wherein the cleaning member S...comprises a conduit adapted to direct fluid through the cleaning member. *05 * S S *. S
13. The cleaning tool of any preceding claim, wherein the cleaning member : comprises at least one port for directing fluid from the tool.S..... S *
14. The cleaning tool of claim 13, wherein the port comprises a nozzle adapted to direct fluid from the tool.
15. The cleaning tool of any preceding claim, wherein at least part of the tool is adapted to facilitate drilling through the tool.
16. The cleaning tool of claim 15, at least part of the tool may be constructed from at least one of aluminium, aluminium alloy, lead, brass, other suitable metallic material; a ceramic material; a polymeric material; a laminate material; carbon fibre; and a glass material.
17. A method of cleaning a downhole tubular component, the method comprising: locating a downhole cleaning tool in a tubular component to be cleaned, the cleaning tool comprising a body; a cleaning member operatively coupled to the body; and a rotary drive arrangement; and operating the rotary drive arrangement to rotate the cleaning member relative to the body to permit cleaning of the tubular component.
18. The method of claim 17, comprising coupling the body to a tubular string. * **

****
19. The method of claim 18, comprising running the tool into the tubular *.*.component with the tubular string. ***. * * * ** 0

**
20. The method of claim 18 or 19, comprising rotating the cleaning member * relative to the string. * * * * *
21. The method of any one of claims 17 to 20, comprising running the tool into the tubular component substantially without rotation.
22. The method of any one of claim 17 to 21, comprising directing fluid through the tool to drive rotation of the cleaning member relative to the body
23. The method of any one of claims 17 to 23, comprising directing fluid through at least one port in the cleaning member.
24. A downhole cleaning tool substantially as described herein and as shown in the accompanying figure.
25. A method of cleaning a tubular component substantially as described herein. * ** 20SS * I 5.. ** * . * S.. S..SSS S. *I