GB2201177A

GB2201177A - Clamp

Info

Publication number: GB2201177A
Application number: GB08804052A
Authority: GB
Inventors: Nicholas Shane Johnston Lake
Original assignee: Wood Group Drilling and Production Services Ltd
Current assignee: Wood Group Drilling and Production Services Ltd
Priority date: 1987-02-21
Filing date: 1988-02-22
Publication date: 1988-08-24
Anticipated expiration: 2008-02-22
Also published as: NO880757L; GB2201177B; NO880757D0; GB8804052D0

Abstract

A clamp for use in clamping conduits (such as power cables and control lines) to tubular structures (such as drill pipe) comprises a first part-annular member (1) for seating on said tubular structure so as to span a coupling thereon and a second part-annular member (4) hingedly connected to said first member and pivotable between an open position and a closed position in which the first and second members define at least part of an annular clamp extending around the tubular structure, the first and second members co-operating to define a passageway (12) extending longitudinally of the tubular structure for receiving power cables and/or control lines. <IMAGE>

Description

'|Clamp" This invention relates to a clamp especially but not exclusively for use in clamping conduits such as power cables and control lines to tubular structures.

In drilling operations various control lines and power cables have to be fastened -to th; outside of a drill string.

Previously this has been achieved by the use of clamps -which are attached around the tubular members forming the drill string. However such clamps are subject to slippage problems which can lead to damage to the control lines and cables.

According to the present invention there is provided a clamp for use in clamping a conduit to a tubular structure comprising a first member for seating on said tubular structure so as to span a coupling thereon and a second member hingedly connected to said first member and pivotable between an open position and a closed position in which the first and second members define at least part of an annular clamp extending around the tubular structure, the first and second members co-operating to define a passageway extending longitudinally of the tubular structure for receiving said conduit.

Preferably, said passageway is formed by radially spaced apart overlapping portions of the first and second members.

Preferably also, said passageway is formed adjacent said hinged connection.

Preferably also, the first and second members co-operate in the closed position to define an annular clamp extending around the tubular structure and are provided with releasable fastening means.

Preferably also, the overlapping portions of the first and second members comprise a lug on said first member extending beyond said hinged connection and a portion of said second member adjacent said hinged connection and spaced radially outwardly from said lug.

Preferably also, at least one of the first and second members comprises two longitudinally spaced end portions interconnected by one or more longitudinally extending bars.

Preferably also, a third member is provided hingedly connected to the second member, the first, second and third members in a closed position defining an annular clamp around the tubular structure, and the first member being engageable with the second member to provide releasable fastening means therebetween.

Preferably also, the releasable fastening means comprises a threaded adjuster.

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a plan view of a first embodiment of a clamp of the present invention, Fig. 2 is a side view of the clamp of Fig. 1 in the direction of arrow A; Fig. 3 is a front view of the clamp of Fig. 1 in the direction of arrow B; Fig. 4 is a sectional view of part of the clamp of Fig. 1 in situ on a tubular taken along the line C-C of Fig. 1 and Fig. 5 is a part sectional plan view of a second embodiment of a clamp of the present invention.

Referring to Figs 1 to 4 of the drawings a cable protecting clamp comprises a first clamp member 1 in the form of a pair of longitudinally spaced apart part circular end members 2 connected by a longitudinal rib 3 and a second clamp member 4 in the form of a pair of longitudinally spaced apart semicircular end members 5 connected by a longitudinal rib 6.

The first and second clamp members are joined together at one edge by a hinged connector 7 and provided with fastening means at the other edge portions in the form of screws 8.

A part of each end member 5 of the second clamp member 4 adjacent the hinged connection 7 is cut away on its inner surface to form a groove 10 into which a lug 11 on each of the end members 2 of the first clamp member 1 extends, beyond the hinged connection 7, to define a channel 12. The lug 11 is tapered so that the channel 12 is at a slight angle.

In use the first clamp member 1 and the second clamp member 2 are pivoted to an open position to allow them to be fitted over a tubular structure. The end members 2 and 5 are positioned at either side of a coupling or upset on the structure with the ribs 3 and 6 extending across the coupling.

A power cable, control line or similar conduit 13 (Fig. 4) is placed against the lugs 11 on the clamp member 1 and the clamp member 2 is closed around the structure to retain the cable or line 13 in the channel 12 thus formed. The screws 8 fasten the clamp members 1 and 2 together. Power cables and control lines are thus retained in position on a tubular structure by the clamp and the risk of slippage is avoided by virtue of the clamp fitting around a coupling. The tapered nature of the lug 11 ensures that the cable is routed smoothly on the structure to prevent damage.

Various adaptations #of the basic clamp can be provided for different applications and the size of the clamps and the materials used will be dependent on the conditions present in each application. Alternative fastening means to the screws 8 are also envisaged.

Clamps may also be produced in which the longitudinal ribs 6 are omitted so that each semi-circular and member 5 is independent.

Referring now to Fig. 5 a second embodiment of a cable protecting clamp is illustrated. This clamp comprises a first member 20 #ingedly connected to a second member 21 which is in turn connected to a semi-circular third member 22 which extends to a fourth member 23 to which it is hingedly connected.

The second member 21 has a pair of grooves 24 formed in its outer surface. These grooves 24 co-operate with part of the first member 20, which ovelaps the second member 21, to define channels 25.

An end formation 26 on the first member 20 connects with a screw threaded adjuster 27 on the fourth member 23.

In use the clamp is pivoted to an open position to allow the members to be fitted over a tubular structure as with the previous embodiment. Power cables and the like can be positioned in the grooves 24 and the clamp closed by engaging the formation 26 on the first member 20 with the threaded adjuster 27 to retain the cables in the channels 25 thus formed.

The clamp is tightened onto the structure by unscrewing the threaded adjuster 27 which tensions the clamp.

In this embodiment, as in the previous embodiment, the clamp operates to fasten the cable and the like against the structure by the simple action of attaching the clamp to the structure.

Modifications and improvement may be incorporated without departing from the scope of the invention.

Claims

1. A clamp for use in clamping a conduit to a tubular structure comprising a first member for seating on said tubular structure so as to span a coupling thereon and a second member hingedly connected to said first member and pivotable between an open position and a closed position in which the first and second members define at least part of an annular clamp extending around the tubular structure, the first and second members co-operating to define a passageway extending longitudinally of the tubular structure for receiving said conduit.

2. A clamp as claimed in Claim 1, wherein said passageway is formed by radially spaced apart overlapping portions of the first and second members.

3. A clamp as claimed in Claim 1 or 2, wherein said passageway is formed adjacent said hinged connection.

4. A clamp as claimed in any one of the preceding Claims, wherein the first and second members co-operate in the closed position to define an annular clamp extending around the tubular structure and are provided with releasable fastening means.

5. A clamp as claimed in any one of the preceding Claims, wherein overlapping portions of the first and second members comprise a lug on said first member extending beyond said hinged connection and a portion of said second member adjacent said hinged connection and spaced radially outwardly from said lug.

6. A clamp as claimed in any one of the preceding Claims, wherein at least one of the first and second members comprises two longitudinally spaced end portions interconnected by one or more longitudinally extending bars.

7. A clamp as claimed in any one of Claims 1 to 3, wherein a third member is provided hingedly connected to the second member, the first, second and third members in a closed position defining an annular clamp around the tubular structure, and the first member being engageable with the second member to provide releasable fastening means therebetween.

8. A clamp as claimed in Claim 7, wherein the releasable fastening means comprises a threaded adjuster.

9. A clamp substantially as hereinbefore described with reference to and as shown in Figs 1 to 4 of the accompanying drawings.

10. A clamp substantially as hereinbefore described with reference to and as shown in Fig. 5 of the accompanying drawings.