GB2121091A

GB2121091A - Control line protector

Info

Publication number: GB2121091A
Application number: GB08314753A
Authority: GB
Inventors: Ben Burton
Original assignee: EDECO DEVELOPMENTS Ltd
Current assignee: EDECO DEVELOPMENTS Ltd
Priority date: 1982-05-27
Filing date: 1983-05-27
Publication date: 1983-12-14
Also published as: GB8314753D0

Abstract

A device for protecting a control line (15, 16) extending down the tubing of a bore hole comprises a collar arrangeable to surround the tubing to lie between the tubing and the cased wall of the bore hole, the collar being shaped to define a protective area (19, 20) for the control line (15, 16) between the tubing and the cased wall of the bore hole. The protective area may be between the tubing and the collar or between the collar and the cased wall of the bore hole. The control line (15, 16) may be held in place on the collar by being deformed by protrusions within the protective area, for example by means of corrugations in the walls of the protective area. Projections (22) may be pressed from the collar to maintain a clearance between the protective area and the cased wall and/or to centralise the collar in the bore hole. <IMAGE>

Description

SPECIFICATION Protecting devices The invention relates to protecting devices and particularly to devices for protecting control lines extending down a bore hole. The term "control lines" as used herein is intended to cover any lines which may extend down a bore hole and will, for example, include electric cables and the like.

Typically a bore hole which has been created by drilling is lined with a casing which is cemented in position. Products from the bore hole are subsequently removed through a smaller coaxial pipe which is passed down the cased bore hole and which is generally referred to as tubing.

After a bore hole has been created, it is frequently necessary to run control lines down the cased bore hole to control equipment at the bottom of the bore hole, for example a pump.

Such control lines may be attached to the tubing but require protection, for example to protect them from abrasion and impact with the cased or uncased wall of the bore hole when the tubing is being installed.

The invention provides a device for protecting at least one control line of a bore hole which control line is intended to extend down the tubing of the bore hole, the protecting device comprising a collar arrangeable to surround the tubing to lie between the tubing and the cased wall of the bore hole, the collar being shaped to define a protective area for the control line between the tubing and the cased wall of the bore hole.

The collar may be shaped to protectively sandwich the control line between the tubing and the collar.

The protective area may be between the collar and the cased wall of the bore hole.

The protective area may be defined between the collar and a cover positioned over the control line.

The control line may be sandwiched between the cover and a reinforcement attached to the exterior of the collar.

The cover may be hinged and may be secured by means of a locking pin.

Circumferential movement of the control line may be restricted by confining at least part of the control line between a pair of radially outwardly extending protrusions situated within the protective area.

There may be means within the protective area which cause the control line to be deformed within the protective area.

The means may comprise a protrusion which causes the control line to deviate from a straight line.

By way of example, specific embodiments of the invention will now be described, with reference to the accompanying drawings, in which: Figure 1 is a plan view of a first embodiment of protecting device according to the invention; Figure 2 is a side view of the device shown in Figure 1; Figure 3 is a plan view of an alternative embodiment of protecting device according to the invention; Figure 4 is a side view of part of the embodiment shown in Figure 3; Figure 5 is a cross-section on line V-V of Figure 4; Figure 6 is a plan view of another embodiment of protecting device according to the invention; Figure 7 is a side view of the device shown in Figure 6; Figure 8 is a plan view of a further embodiment of protecting device according to the invention; Figure 9 is a side view of the device shown in Figure 8; and Figure 10 is a cross-section on line X-X of Figure 9.

The protecting device shown in Figures 1 and 2 comprises a collar formed in two generally semicircular halves 10 and 1 The halves can be fitted together around the cylindrical tubing (not shown) extending down a cased bore hole (not shown).

The halves are formed into shape from blanks cut from steel sheet. The blanks are shaped so that they have a plurality of spaced-apart tongues 12 which are bent back on themselves to define holes 13. The positioning of the tongues 1 2 is such that the respective tongues of the two halves 10 and 11 can be interdigitated as shown in Figure 2 in the manner of a hinge, and the two halves can then be locked together by inserting locking pins 14.

The object of the collar is to protect two control lines which, in use, will pass down the length of the bore hole. Two such control lines are illustrated in Figure 1 by the reference numerals 15 and 16.

The part 11 of the collar is deformed radially outwardly at 1 7 and 1 8. Thus if the collar is clamped around tubing, the deformations 1 7 and 1 8 will co-operate with the outer wall of the tubing to define two passages 1 9 and 20 which will extend parallel to the longitudinal axis of the bore hole and which can accommodate the control lines so that the control lines are protectively sandwiched between the collar and the tubing.

External reinforcement is provided for the .deformations 17 and 18 in the form of a shallow channel section 21 which is welded over the deformations.

The collar is provided with four radially outwardly extending projections 22 which are formed by deforming the walls of the parts of the collar radially outwardly.

These projections fulfill four functions. Firstly they tend to centralise the collar, and hence the bore hole tubing, in the bore hole. Secondly the projections of the part 1 which abut the cased bore hole on either side of the deformations 1 7 and 18, provide a clearance between the deformations and the cased bore hole, thus reducing the risk that the deformations, and the control lines within, will be damaged by engagement with the cased bore hole.

Thirdly, the projections similarly provide a clearance between the hinge-like connections 1 2 and 14 and the wall of the cased bore hole, protecting the connections from damage and wear.

Fourthly, the projections 22 are provided with means for clamping the collar to the tubing. A hole 23 is drilled through each projection and within each projection there is welded a threaded insert 24. Thus bolts (not shown) can be screwed into the captive insert 24 to abut against the wall of the tubing.

If the bolts are screwed in very tightly, this puts the collar under considerable circumferential tension, tending to straighten out the deformations 1 7 and 1 8. However the reinforcement 21, in addition to providing external protection for the deformations, helps to reduce the tendency for the deformations to straighten out.

Turning now to Figures 3, 4 and 5, an alternative embodiment is shown which is particularly suitable for protecting a control line in the form of a large diameter electric able 25, as well as three smaller diameter control lines 26.

In this case one part 27 of the collar is substantially semi-circular but the other part 28 has a considerable deformation 29 extending radially outwardly. A rubber or other resilient insert 30 is shaped to fit between the tubing 31 and the deformation 29. The insert 30 has a large slot 32 therein to accommodate the cable 25 and it also has three smaller slots 33 therein which cooperate with the tubing 31 to define passages to protectively receive the control lines 26.

As with the embodiment shown in Figures 1 and 2, the two halves of the collar are pinned together, but instead of forming hinge-like interconnections by the deformation of tongues, each half of the collar is provided with circumferentially extending ribs 34 as shown in Figures 4 and 5. The dimensions of the ribs 34 on one of the halves are slightly less than those on the other half so that the ribs can be fitted together as shown in the cross-section in Figure 5, and then a locking pin 35 can be inserted through holes provided in the ribs.

At the side of the collar shown in Figures 4 and 5, only a single set of holes is provided. At the other side however, as shown at the top of Figure 3, each half of the collar is provided with three holes 36. The holes in one half have different spacings to the holes in the other half and this enables the position of one half of the collar to be adjusted towards and away from the other half by a certain extent. As shown in Figure 3, the central hole of one half is in register with the central hole of the other half, so that a locking pin can be passed through, but it is possible to put different holes into register with one another to move the two halves of the collar closer together or further apart.

This makes it possible to adjust the extent to which the insert 30 is compressed. Alternatively or in addition, it is possible to accommodate lengths of tubing 31 of slightly different dimensions.

Turning now to Figures 6 and 7 another embodiment is shown which is particularly useful for protecting small diameter control lines. The construction of the device is somewhat similar to that shown in Figures 1 and 2 and similar parts are labelled with like numerals. As in the first embodiment, a collar is formed in two generally semi-circular halves 10 and 11 which are provided with spaced apart, interdigitating tongues 1 2 which define holes 1 3 allowing locking pins 14, 1 4a to be inserted, thus securing the collar around the tubing (not shown). Pin 14 is kept permanently in position and acts as a hinge, whereas pin 1 4a performs the locking and unlocking. Four outwardly extending projections 22 are provided on the collar by deformation of the collar walls.

Welded on to the exterior face of half 11 is a plate 40 which is shaped to fit over part of the half 11. Towards both the top and the bottom of plate 40 are struck out a pair of radially outwardly extending tongues 41. Also struck out in the centre of the plate 40 is another tongue 42 which also extends radially outwardly. Tongue 42 lies substantially along the longitudinal axis of the plate 40. The opposing tongue 41 of each pair define a passage which can accommodate two control lines 43 as a tight fit therein. The lines will usually have sufficient flexibility to allow them to pass one either side of tongue 42. Thus, when the lines are pushed inbetween tongues 41 and around tongue 42 they will be tightly held on the collar. In other words the slightly undulating path that the lines follow increases the frictional grip upon them.

Plate 40 is provided with a plurality of spaced apart tongues 44 which are bent back on themselves in a similar manner to the tongues 12.

A covering plate 45 fits over the welded-on plate 40 and is provided with tongues 46, like the tongues 44 of plate 40, and the two sets of tongues on the plates interdigitate and are secured by passing locking pins 47, 48 through the holes defined by the tongues.

Locking pin 47 is kept permanently in place and acts as a hinge but locking pin 48 is provided with a head 49 and a tapered point 50 in order to facilitate removal and insertion. The plate 45 is designed so that when secured to plate 40 by the pins 47, 48, the plate 45 presses firmly against control lines 43 which are thus securely held in place on the collar.

Two holes 51 are provided in each projection 22 and welded into each hole 51 is a threaded insert 52. Thus grubscrews 53 can be screwed into the inserts 52 to abut against the wall of the tubing and thus clamp the collar to the tubing.

Even if the grubscrews are screwed in very tightly, the control lines 43 are firmly held between the two plates 40 and 45. A good frictional grip is on the control lines is important, because long lengths of control line can of course have considerable weight.

Referring now to Figures 8, 9 and 10 a further embodiment is illustrated, which is particularly useful for protecting large diameter control lines, such as that indicated at 54. As in the previous embodiment, a collar is formed in two generally semi-circular halves 10, 11 which are provided with spaced apart, interdigitating tongues 12 defining holes 13 which receive locking pins 14, thus securing the collar around the tubing (not shown). Again, pin 14 is kept permanently in place acting as a hinge and pin 1 4a is used to lock and unlock the collar. Also, as in the previous embodiment, a plate 40a, shaped to fit around part of the exterior of half 11 of the collar is welded to the half 11.

As best seen in Figure 10, plate 40a is provided with a plurality of corrugations 55 which space the plate slightly from the half 11 of the collar in its central region. The plate 40a generally lies flush against the half 11 of the collar, but is deformed to provide two U-shaped longitudinal ribs 56 which are cut away at several locations 57. A generally U-shaped cover plate 58 fits around the plate 40a but spaced apart therefrom.

The cover plate 58 is provided with a plurality of spaced apart tongues 59 which are bent back on themselves similar to tongues 12 to provide holes 60. The tongues 59 fit into the cut away portions 57 and the cover plate 58 and plate 40a are secured together by inserting locking pins 61, 62 along the ribs 56 and through the holes 60. As before, locking pin 61 is kept permanently in place and acts as a hinge whereas the cover plate 58 is secured and released by pin 62, which is provided with a loop 63 for easy handling. As seen in Figures 9 and 10 the cover plate 58 is provided with corrugations 64 at its top and bottom. A second cover plate 65 is welded on to the outside of cover 58 to provide a smooth outer surface and give added protection.

In use, the outer cover 58 is swung open and the control line 54 is positioned against the plate 40a. The cover 58 is then swung closed and the locking pin 63 is inserted. The line 54 is a very tight fit within the gap between the cover 58 and the plate 40a, and the fit is made even tighter by the provision of the corrugations 55, 64 which squeeze the line and make it follow an undulating path through the gap, as best seen in Figure 10.

This again provides good frictional grip on the line.

Considerable force is needed to squeeze the line 54 and to align holes 60 with ribs 56 allowing locking pin 62 to be inserted, and a C-spanner 66 purchasing on the second outer cover 65 may be used for this purpose.

Only two projections 22 are used in this embodiment. Two holes 51 are provided in each projection 22 and are provided with a welded-in threaded insert 52, allowing grubscrews 53 to clamp the collar to the tubing (not shown) as before. Since the control line cover abuts the lining of the bore hole in use, the second outer cover 65 is used in order to further reduce the risk of damage to the control line 54.

The invention is not restricted to the details of the foregoing embodiments.

Claims

1. A device for protecting at least one control line of a bore hole which control line is intended to extend down the tubing of the bore hole, the protecting device comprising a collar arrangeable to surround the tubing to lie between the tubing and the cased wall of the bore hole, the collar being shaped to define a protective area for the control line between the tubing and the cased wall of the bore hole.

2. A device as claimed in Claim 1, in which the collar is shaped to protectively sandwich the control line between the tubing and the collar

3. A device constructed and arranged substantially as herein described, with reference to Figures 1 and 2, Figures 3, 4 and 5, Figures 6 and 7 and Figures 8,9 and 10 of the accompanying drawings.

3. A device as claimed in Claim 1, in which the protective area is between the collar and the cased wall of the bore hole.

4. A device as claimed in Claim 3, in which the protective area is defined between the collar and a cover positioned over the control line.

5. A device as claimed in Claim 4, in which the control line is sandwiched between the cover and a reinforcement attached to the exterior of the collar.

6. A device as claimed in Claim 5, in which the cover is hinged and may be secured by means of a locking pin.

7. A device as claimed in Claim 5, or Claim 6, in which circumferential movement of the control line is restricted by confining at least part of the control line between a pair of radially outwardly extending protrusions situated within the protective area.

8. A device as claimed in any one of Claims 1 to 7, in which there are means within the protective area which cause the control line to be deformed within the protective area.

9. A device as claimed in Claim 8, in which the means comprise a protrusion which causes the control line to deviate from a straight line.

10. A device as claimed in Claim 9, in which there are two control lines, which pass around the protrusion on opposite sides thereof.

11. A device as claimed in Claim 8 or Claim 9, in which the means comprise a deformation of at least part of the material defining the protective area.

12. A device as claimed in any one of Claims 8 to 11, in which the control line is deformed radially.

13. A device as claimed in any one of Claims 1 to 12, in which the collar is reinforced externally of the protective area to protect the protective area against abrasion and/or to reduce any tendency for the collar to straighten out in the region of the protective area.

14. A device as claimed in any one of the preceding claims, in which the collar has at least two radially outwardly extending projections, one at each side of the protective area, such that in use the projections abut the cased wall of the bore hole to maintain a clearance between the protective area and the cased wall of the bore hole.

15. A device as claimed in Claim 14, in which there are more than two projections and the projections are arranged to centralise the collar in the bore hole.

16. A device as claimed in Claim 15, in which there are four projections.

1 7. A device as claimed in any one of Claims 14 to 16, in which each projection is formed by deforming part of the wall of the collar radially outwardly.

18. A device as claimed in Claim 17, in which each projection is formed by a pressing operation.

19. A device as claimed in any one of Claims 1 to 18, in which there are means to clamp the collar to the tubing, to enable collars to be positioned at any point along the length of the tubing installed in the bore hole.

20. A device as claimed in Claim 19, in which the means comprise at least one threaded member which can be screwed through a threaded hole in the collar to abut against the tubing.

21. A device as claimed in Claim 20 when appendant to Claim 14, in which there is a threaded hole in each projection, each threaded hole receiving a threaded member.

22. A device as claimed in Claim 21, in which the threaded holes are provided by welding a female threaded insert inside each projection.

23. A device as claimed in any one of Claims 1 to 22, in which the collar is formed in two halves connectable together around the tubing.

24. A device as claimed in Claim 23, in which the two halves are connectable together by means of locking pins.

25. A device as claimed in Claim 24, when appendant to Claim 14, in which the said radially outwardly extending projections are arranged to provide a clearance between the locking pins of the collar and the cased wall of the bore hole, to protect from abrasion the connections between the two halves.

26. A device as claimed in any one of Claims 23 to 25, in which there are means to move the two halves towards and away from one another to vary the clamping pressure between the collar and the tubing and/or enable the collar to be fitted to slightly different sizes of tubing.

27. A device as claimed in Claim 26, in which one connection beneath the two halves comprises a single hinge and the other connection comprises an adjustable locking pin.

28. A device as claimed in Claim 27, in which the locking pin is insertable through any one of a plurality of locking holes.

29. A device as claimed in any one of Claims 1 to 28, in which the wall of the collar is formed radially outwardly at at least one circumferential location to define with the outer wall of the tubing a passage extending in the direction of the longitudinal axis of the tubing to accommodate a control line.

30. A device as claimed in Claim 29, in which where the collar is formed radially outwardly, an insert is provided to fit within the collar at the said location to assist in locating the control line.

31. A device as claimed in Claim 30, in which the insert is of resilient protective material.

32. A device as claimed in Claim 31, in which the insert is of rubber.