GB2540538A

GB2540538A - Control line clamp system

Info

Publication number: GB2540538A
Application number: GB1512395.3A
Authority: GB
Inventors: Erik Steine Ken; Klausen Morten; Hetland Lasse
Original assignee: ACE OIL TOOLS
Current assignee: ACE OIL TOOLS
Priority date: 2015-07-15
Filing date: 2015-07-15
Publication date: 2017-01-25
Also published as: WO2017009440A1; GB201512395D0

Abstract

A clamp 100 is attachable to a pipe 102, the clamp comprising a body 113, and at least one gripper 104 for attaching the clamp 100 to a pipe 102, such that by only pressing the clamp 100 against the pipe 102 the at least one gripper 104 attaches the clamp 100 to the pipe 102. The grippers 104 may inter-engage with collars 107 mounted to the pipe 102 alongside a joint 115. The clamp my form a conduit protecting wire(s) such as control line 118 passing the joint 115. The collar 197 and gripper 104 may include inter-engaging teeth 108. A clamp 100 may comprise grippers 104 at either end of an elongate body 113, or may have a single gripper (104, figure 3). A method of attaching the clamp 100 to a pipe 102 may include the use of a laser alignment guide.

Description

CONTROL LINE CLAMP SYSTEM

Field

The field of the present invention relates to a clamp for attachment to a pipe. The clamp is arranged to hold one or more wires against the pipe and to provide a protective sheath for the one or more wires across a junction between ends of pipes on a pipe string. Advantageously, the clamp can be quickly and easily attached to a pipe by only pressing the clamp against the pipe.

Background

The extraction of hydrocarbons, such as oil and gas, from subsea oil and gas deposits involves a multiple stage process requiring an array of different machinery and tools. After the drilling of the wellbore has been completed a completion string is inserted into the well to allow the flow of hydrocarbons from the reservoir to a subsea wellhead on the sea floor and then onto a surface wellhead above the surface of the sea. This completion string is not one long section of pipe and is formed of a series of sections of pipes connected together to form one flow channel.

Wired connections between the surface wellhead and the subsea wellhead are necessary for providing communication, enabling control of tools and for monitoring conditions such as temperature and pressure from sensors. This functionality is provided by control lines that may communicate by electric, fibre optic, hydraulic, pneumatic, or any other type of signals.

The control lines run on the outside of the pipe stem, from the surface wellhead down to the subsea wellhead. It is a requirement that these control lines remain under tension throughout their use. The control lines also have to be protected to ensure that they are not damaged resulting in the loss of any signal being transmitted. During the process of attaching multiple pipes together this can be problematic as tension may be lost or damage may occur to the surface of the control lines. In particular, control lines are vulnerable to damage by the weld joint linking the two pipe segments as the diameter at these joints is larger than the diameter of the rest of the pipe.

It is known in the art to provide a sheath or clamp system to hold cables to the surface of the pipe string and to provide a protective bridge for the cables across the junction between pipes. However, these known devices require welding or a screw mechanism to attach the sheath or clamp system to the pipe and these are slow and expensive operations.

It is therefore desirable to improve on known techniques for clamping control lines to a pipe string.

Summary of Invention

According to a first aspect of the invention, there is provided a clamp that is attachable to a pipe, the clamp comprising a body and at least one gripper for attaching the clamp to a pipe, such that by only pressing the clamp against a pipe the at least one gripper attaches the clamp to the pipe.

Preferably the body of the clamp has the same radius of curvature as the pipe that it is attachable to, such that the clamp provides a tight fit when pressed against the pipe.

Preferably the clamp body comprises a section for spanning across a junction between two connected pipes.

Preferably the at least one gripper is arranged to grip to a collar surrounding the pipe.

Preferably the at least one gripper comprises one or more teeth for attaching the clamp to a pipe.

Preferably the at least one gripper is in the form of a mechanical press fit.

Preferably the at least one gripper is provided at an end of the clamp body.

Preferably the clamp is substantially elongate and there are at least first and second grippers, the first and second grippers being provided at the same end of the clamp and on opposite sides of the clamp.

Preferably the body comprises slits on either of each gripper.

Preferably the clamp comprises at least one gripper at each end of the body, such that said section for spanning across a junction between two connected pipes is in between the at least one gripper provided at each end of the body.

Preferably the clamp is for clamping wires to a pipe.

Preferably the wires are control lines.

Preferably the clamp comprises one or more conduits for wires, the conduits being provided along the length of the clamp.

Preferably the clamp body is chamfered.

Preferably the clamp body comprises one or more holes for receiving one or more further attachment devices to the pipe.

Preferably the clamp comprises a lip for restricting axial movement of the clamp.

According to a second aspect of the invention, there is provided a collar for surrounding a pipe, the collar comprising at least one clamp for attaching the collar to a pipe and at least one groove on the exterior surface of the collar, such that a device is attachable to the collar by a gripper of the device engaging with the at least one groove when the device is only pressed onto the collar.

Preferably the collar comprises a first and second portion in a male to female fit, wherein receiving the first portion into the second portion causes the at least one clamp to engage with the pipe such that the collar is attached to the pipe.

Preferably a surface of the first portion is external to the male female fit, and said surface comprises the at least one groove.

Preferably the at least one groove is on the exterior surface of the second portion.

Preferably the collar comprises one or more identification marks for use in aligning the device for attachment with the collar.

Preferably the collar comprises recesses on its exterior surface for providing further attachments to the collar than by the at least one groove.

Preferably the device attachable to the collar is the clamp according to the first aspect of the invention.

According to a third aspect of the invention there is provided a pipe clamp system comprising a collar attached to a pipe and a clamp attached to the collar, wherein the attachment between the clamp and collar is achieved by only pressing the clamp against the collar.

Preferably the clamp is the clamp according to the first aspect of the invention.

Preferably the collar is the collar according to the second aspect of the invention.

Preferably the clamp comprises one or more conduits, for one or more wires, the conduits being provided along the length of the clamp, for spanning across a junction between two connected pipes.

Preferably the wire is a control line and the pipe is for use in the subsea oil industry.

According to a fourth aspect of the invention there is provided a method of attaching a clamp to a pipe, comprising pressing a clamp against a pipe so as to cause one or more grippers comprised by the clamp to engage into a gripping action, such that, by only pressing the clamp against the pipe, the clamp is held to the pipe.

Preferably the method further comprises attaching a collar to the exterior of a pipe; wherein the pressing of the clamp against the pipe comprises pressing the clamp against the collar, wherein the one or more grippers of the collar engage one or more grooves of the collar.

Preferably the method further comprising aligning the one or more grippers of the clamp and the one or more grooves of the collar prior to pressing the clamp against the collar.

Preferably the method further comprising using a guiding mechanism to align the clamp and the collar such that the one or more grippers are aligned with the one or more grooves.

Preferably the guiding mechanism further comprises using an identification mark on the collar.

Preferably the guiding mechanism further comprises using laser guiding to ensure the one or more grippers of the clamp are aligned with the one or more grooves of the collar.

Preferably the clamp is pressed to the exterior of the collar by a hydraulic press.

Preferably the method further comprising providing further attachment means through holes in the clamp and receiving said attachment means in recesses on the collar.

Description of Drawings

Figure 1 shows a pipe clamp system according to a first embodiment of the invention.

Figure 2 shows a pipe clamp system according to a first embodiment of the invention.

Figure 3 shows a pipe clamp system according to a first embodiment of the invention.

Figure 4 shows a pipe clamp system according to a second embodiment of the invention.

Figure 5 shows a pipe clamp system according to a second embodiment of the invention.

Figure 6 shows a pipe clamp system according to a third embodiment of the invention.

Figure 7 shows a flowchart of a method of attaching a clamp to a pipe according to an embodiment of the invention.

Detailed Description

Embodiments of the present invention provide a clamp, a clamp system and a method for clamping a wire to a pipe. The clamp according to embodiments comprises a conduit for control lines between the joint region connecting two pipes. The clamp is particularly suitable for oil industry applications, such as for supporting cables between surface and subsea wellheads, and overcomes at least some of the problems experienced by known clamping techniques for this purpose.

Embodiments of the present invention will now be described with reference to the drawings. Figures 1 to 3 illustrate the pipe clamp system 100 according to a first embodiment of the present invention. The system comprises a clamp 101 that is attachable to a pipe 102. The clamp 101 comprises a body 103 that extends down the axial length of the pipe 102 when clamped onto the pipe 102 with the clamp body 103 being substantially elongate.

As can be seen in Figures 1 to 3, gripping portions, i.e. grippers 104, provide a means of attaching the clamp 101 to the pipe 102. In the embodiment shown in Figures 1 to 3, the clamp 101 comprises only two grippers 104, both grippers 104 being located at the same end of the clamp body 103 and on opposite sides of the clamp body 103.

The clamp body 103 comprises a middle section 105 for extending axially along the length of a pipe 102. The middle section 105 is arranged to provide a bridge over a connection between two pipes 102. Preferably, at least the middle section 105 of the clamp 101, and more preferably the entire length of the clamp 101, comprises conduits 106 for holding cables.

The clamp body 103 preferably comprises a chamfered cross-section. Advantageously, the chamfered cross-section increases the gripping force applied by the clamp 101 and therefore strengthens the attachment of the clamp 101 to the pipe 102. This reduces the axial and rotational displacement of the clamp 101 when it is attached to a pipe 102. A collar 107 is attached to the pipe 102 and the clamp 101 is arranged to attach to the collar 107. The collar 107 surrounds the pipe 102 and forms the attachment region on the pipe 102 for the clamp 101. Preferably, the collar 107 is provided with one or more grooves 108 on its exterior surface and the grippers 104 of the clamp 101 are arranged to engage with the grooves 108 of the collar 107 so as to attach the clamp 101 to the collar 107.

The collar 107 preferably comprises a first portion 109 and a second portion 110. The first portion 109 is shaped to receive the second portion 110 in a male-female fit. The receiving of the first portion 109 by the second portion 110 causes fingers 111 of the first portion 109 of the collar 107 to be forced in a radial direction in towards the pipe 102 and clamps the collar 107 to the pipe 102. This is clearly shown in Figure 2 where the collar fingers 111 located on the first portion 109 are forced in the radial direction towards the pipe 102 by the interference fit with the second portion 110.

In a particularly preferred embodiment, the collar 107 is a collar 107 as described in W02014/011056A1.

The attachment between the collar 107 and the clamp 101 is provided by pressing the clamp 101 onto the collar 107 such that the grippers 104 of the clamp 101 engage the grooves 108 on the external surface of the collar 107 to thereby attach the clamp 101 to the collar 107.

Advantageously, by only having grippers 104 at one end of the clamp body 103 increases the ease of attachment of the clamp 101 to the pipe 102 as only one set of grippers 104 needs to be correctly aligned with the attachment to the collar 107 on the pipe 102.

The gripper is formed on the body 103 of the clamp 101. Preferably, the body 103 of the clamp 101 has the same or similar radius of curvature as the pipe 102 to be attached to such that it provides a tight fit when pressed against the pipe 102 and collar 107.

The gripper may comprise one or more teeth extending out from the body 103 of the clamp 101 for providing the gripping. The teeth align and engage with grooves 108 on the collar 107 providing interlocking portions that hold the clamp 101 and collar 107 together. The teeth may be provided on one side of the clamp 101, on opposite sides of the clamp 101, or in other embodiments the teeth may be provided around the interior circumference of the clamp 101 to provide multiple regions of interference between the clamp 101 and the collar 107. The teeth may be any shape of teeth known in the art including rectangular, ridged, and hooked. The grooves 108 of the collar 107 are shaped to engage with the teeth so to provide attachment of the clamp 101 to the collar 107. Advantageously, providing a plurality of teeth around the circumference of the clamp 101 increases the strength of the attachment to the pipe 102 and thereby reduces rotational movement and slipping of the clamp 101 in the circumferential direction of the pipe 102 when attached to the collar 107.

The gripper preferably attaches to the grooves 108 on the collar 107 by a ratchet type mechanism. In other embodiments the nature of the attachment may be any type of interference fit, or any type of mechanical fit.

On either of each gripper, circumferential slits may be provided from the edges of the clamp 101. In the embodiment shown in Figure 1, two slits 112 are provided, one on each side of each gripper. Advantageously, the slits 112 increase the elasticity of the gripper and aid the attachment of the clamp 101 to a collar 107 on a pipe 102.

The grooves 108 on the collar 107 extend in the axial direction of the pipe 102 as can be seen in Figure 1. In the preferred embodiment a plurality of grooves 108 are arranged around the whole circumference of the collar 107. Advantageously, this results in it being easier to align the clamp 101 and collar 107 prior to attachment. In alternative embodiments there may be fewer grooves 108, for instance one groove requiring a specific alignment of the clamp 101 and collar 107.

The grooves 108 may be provided on the first portion 109 of the collar 107, as can be seen in the embodiment disclosed in Figures 1 to 3, on a region that is external to the attachment section between the first and second portions 109/110 in the male to female fit. Embodiments include the grooves 108 alternatively being provided on the second portion 110 of the collar 107, as can be seen in the embodiment disclosed in Figures 4 and 5. Embodiments also include the groves being provided on both the first and second portions 110 of the collar 107.

Holes 113 may be provided in the clamp body 103 and/or collar 107 to provide additional attachment to the pipe 102 or collar 107. After a press attachment of the clamp 101 to the collar 107 has been implemented, further means of attachment may be provided through the holes 113. This may be a screw, pin or any other method of attachment known in the art and may attach to the collar 107 or directly onto the pipe 102. The attachment may extend radially through the collar 107. Corresponding recesses 114 may be formed on the collar 107 or pipe 102 for receiving said attachment. The holes 113 may be located at either end of the body 103 of the clamp 101 as shown in Figures 1 to 3 or at any other location along the clamp 101. Typically two holes 113 will be provided at either end of the clamp 101; however any number or arrangement of holes 113 may be present. Advantageously, this additional attachment helps to prevent the slipping of the collar 107 axially or radially and provides additional support for the attachment. A second embodiment of the present invention is shown in Figures 4 and 5. This embodiment has many features in common with the first embodiment with like features having corresponding reference signs.

In the second embodiment the clamp 101 comprises grippers 104 at both ends of the elongate clamp body 103. Two collars 107 are provided on the pipe 102, one for attaching to each gripper. In the second embodiment the clamp body 103 has a middle section 105 linking between the grippers 104 at each end of the body 103. The middle section 105 provides a bridge between ends of the clamp 101. The section linking both ends of the body 103 of the clamp 101 is for spanning across a junction 115 between two pipe 102 sections at a pipe joint. As shown in Figures 4 and 5, the middle section 105 of the clamp 101 may have a cut away profile 116.

An advantage of the second embodiment is that the one or more grippers 104 provide attachments at both ends of the body 103 of the clamp 101 and this strengthens the attachment of the clamp 101 to the pipe 102. However, if two collars 107 are provided on the pipe 102 it is necessary for these to be correctly spaced apart from each other along the longitudinal axis of the pipe 102. The first embodiment does not have the advantage of both end of the clamp 101 having attachments to the pipe 102 but the process of attaching the clamp 101 of the first embodiment to the pipe 102 as easier and cheaper because only one collar 107 is used.

The clamp 101 of the second embodiment differs from the clamps as described for the first embodiment only by having one or more grippers 104 at each end of the clamp 101. The clamp 101 according to the second embodiment may also have any of the features as described for the first embodiment, such as one or more holes 113 on the clamp 101 and/or collar 107 for further attachment devices to the pipe 102.

Preferably, the clamps 101 of the first and/or second embodiments comprise a lip 117 extending from the body 103 of the clamp 101, which helps to prevent axial movement of the clamp 101 along the pipe 102. The lip 117 can contact the collar 107 of the pipe 102 to prevent movement in the axial direction between the clamp 101 and pipe 102. Alternatively the lip 117 may engage the pipe junction 115, or the pipe 102 itself, to prevent the axial movement.

Preferably, the clamps 101 of the first and/or second embodiments acts as a support for a further device 119, as shown in Figure 6. The device 119 spans the length of the clamp 101 with attachment to the pipe either side of the clamp 101. The device 119 is attached to the clamp via a series of attachment means 121. The attachment means 121 are received in the holes 113 on the clamp to ensure secure attachment. The attachment means 121 may be a screw, pin or any other method of attachment known in the art.

Preferably, the clamps 101 of the first and/or second embodiments comprise a gripper portion 104 that is detachable from the clamp 101. Holes in the gripper portion 104 as shown in Figures 1 to 6 provide a means of attachment for a detachable gripper plate to the underside of the gripper portion 104. The gripper plate comprises the one or more gripper teeth. Advantageously having a detachable gripper plate allows grippers with teeth of various sizes to be attached to the clamp permitting attachment to various sizes of pipes or collars.

According to an embodiment, the clamp 101 is for clamping wires to a pipe 102 and one or more conduit is provided along the length of the body 103 of the clamp 101 through which wires, i.e. cables/control lines 118, can pass. These conduits 106 and control lines 118 are shown in Figures 4 and 5. The embodiments shown in Figures 1 to 3 and 6 preferably also comprise one or more conduits 106 but this not shown in the drawings.

Embodiments are particularly suitable for applications in the oil industry with each clamp 101 attaching to a pipe 102 between surface and subsea wellheads and for securely holding one or more control lines 118. Each clamp 101 is preferably provided at junctions 115 between pipes with the clamp 101 providing a bridge over the junction 115 so that the control line is protected.

In a preferred implementation, the clamp 101 has conduits 106 for up to twelve control lines 118, however any number of conduits 106 may be provided depending on the number of control lines 118 that it is necessary to hold. The conduit is preferably passed internally through the clamp 101. However in alternative embodiments, the conduit may be located underneath the clamp 101 so that the control lines 118 pass between the clamp 101 and the pipe 102. Each clamp 101 provides protection of the control lines 118 from impacts and prevents damage and crushing of the control lines 118, in addition to holding the control lines 118 in place.

The control lines 118 may communicate by electric, fibre optic, hydraulic, pneumatic, or any other type of signals and provide communication, enabling the control of tools and the monitoring of conditions such as temperature and pressure from sensors.

The clamp 101 and/or collar system may be made from any material known for manufacturing clamps and collars in the oil industry, such as steel. For high performance applications, the clamp 101 and/or collar 107 may be made of any type of metal or metal alloy including superalloys, such as Inconel®. The pipe 102 segments are preferably welded together, however any means of joining pipes can be used.

Pipe junctions 115 have a diameter larger than the diameter of the rest of the pipe 102. Advantageously, the clamp 101 provides protection for the control lines 118 across a pipe junction 115 and ensures that the control lines 118 are maintained at the correct tension.

In another embodiment, the collar 107 may comprise grooves 108 on both the first and second portions 109/110 of the collar 107 so that two separate clamps can be attached to the same collar 107. The two clamps attached to the same collar 107 extend axially along the pipe 102 in opposite directions from each other. A plurality of such collars and clamps may be provided substantially along the entire length of the pipe 102.

The method of attaching a clamp 101 according to embodiments to a pipe 102 is performed by an attachment system. The pipe 102 first has one or more collars 107 attached to it. The attachment system is then arranged to attach a clamp 101 to the collar 107 on the pipe 102 by being configured to: - hold the clamp 101 relative to the pipe 102; - align the clamp 101 with one or more collars 107 that are already attached the pipe 102; and - press the clamp 101 against the pipe 102 so as to cause one or more grippers 104 on the clamp 101 to attach to the one or more collars 107.

The attachment system clamp 101 may comprise a hydraulic press for forcing the clamp 101 against the pipe 102 so that the grippers 104 of the clamp 101 engage with the grooves 108 of the one or more collars 107 attached to the pipe 102.

The pressing of the clamp 101 onto the collar 107 is preferably in a direction radial to the pipe 102. However, embodiments include the pressing of the clamp 101 to the collar 107 also comprising a rotation of the pipe 102 whilst said pressing in the radial direction is performed. This may be necessary if, for example, the grippers 104 comprise a hook profile.

To aid in the attachment of the clamp 101 to the collar 107 there may be provided a guiding mechanism to ensure the clamp 101 and the collar 107 are aligned correctly prior to the clamp 101 being pressed against the pipe 102. The guiding mechanism is provided to ensure that the grippers 104 of the clamp 101 and the grooves 108 of the collar 107 align, for instance by aligning the teeth of the grippers 104 and the grooves 108 of the collar 107. This may be advantageous in embodiments where the grooves 108 and grippers 104 may only favour one particular orientation of clamp 101 and collar 107, such as when there is only one groove on the collar 107. The guiding mechanism may be in the form of one or more identification marks on the collar 107 that can be used as markers to ensure that the collar 107 and clamp 101 are aligned in the correct arrangement. These markers provide a visual aid in the alignment. Embodiments also include the guiding mechanism using laser guiding to align the clamp 101 and collar 107. The laser guiding may use the one or more identification marks on the collar 107 to aid in the alignment.

The pipe clamp system 100 according to embodiments is highly suited to the clamping of control lines 118 to a pipe 102 in subsea oil and gas applications. Embodiments allow the clamp 101 to be attached to a pipe 102 in an easier manner than by conventional clamp systems known in the art. The pipe clamp system 100 is attached by only pressing the clamp 101 against the pipe 102, such that the grippers 104 hold the clamp 101 to the pipe 102, in contrast to clamp systems known in the art that rely on more complicated attachment techniques.

Advantageously, the clamp system 100 according to embodiments provides a conduit for control lines 118, in particular across a pipe joint. The conduit provides protection of control lines 118 from external impact or damage. The clamp system 100 according to embodiments further prevents damage to the control lines 118 from a loss of tension, with the clamp 101 ensuring a constant tension is achieved across pipe joints, where the diameter of the pipe 102 is larger than the rest of the pipe 102 which causes strain on the control lines 118 and damages them.

Another advantage is that the clamp 101 is easily attached to a pipe 102 by only pressing the clamp 101 against the pipe 102. No welding or screwing is required to attach the clamp 101 to the pipe 102.

Figure 7 is a flowchart of a method of attaching a clamp 101 to a pipe 102 according to an embodiment.

In step 701, the process begins.

In step 703, a clamp 101 is pressed against a pipe 102 so as to cause one or more grippers 104 comprised by the clamp 101 to engage into a gripping action, such that by only pressing the clamp 101 against the pipe 102, the clamp 101 is held to the pipe 102.

In step 705, the process ends.

Many modifications and variations may be made to the above-described embodiments within the scope of the invention.

It is not necessary for the clamp 101 to have a chamfered cross-section and embodiments include alternative cross-sectional shapes of the clamp 101, such as a circular arc.

Embodiments include alternative designs of collar 107. For example, the collar 107 may have any means of attachment to the pipe 102 and may, for example, be welded to the pipe 102.

At the ends of the clamp 101 where grippers 104 are provided, the clamp 101 may comprise gripers on both sides of the clamp 101 or, alternatively, a griper may only be provided on one side of the clamp 101.

In the above described embodiments, a slit is provided on each side of each gripper. However, embodiments include only one slit being provided or more than two slits 112 being provided.

When attaching the clamp 101 to the pipe 102, the process of aligning the clamp 101 with a collar 107 attached to the pipe 102 is optional and may not be necessary. For example, the clamp 101 may be able to attach to the collar 107 in all rotational alignments of the clamp 101 and collar 107 or the clamp 101 and/or collar 107 may be configured to rotate into a correct alignment by the contact of the clamp 101 with the collar 107.

It is not essential fora collar 107 to be provided on a pipe 102 for the clamp 101 to be attachable to the pipe 102. The grippers 104 of the clamp 101 may be able to attach directly to the pipe 102. The grippers 104 may be able to attach to a smooth external surface of pipe 102 or the pipe 102 may have groves formed in its exterior surface to enable the clamp 101 to directly attach to the pipe 102.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. In addition, where this application has listed the steps of a method or procedure in a specific order, it may be possible, or even expedient in certain circumstances, to change the order in which some steps are performed, and it is intended that the particular steps of the method or procedure claims set forth herebelow not be construed as being order-specific unless such order specificity is expressly stated in the claim.

Claims

CLAIMS:

1. A clamp that is attachable to a pipe, the clamp comprising: a body; and at least one gripper for attaching the clamp to a pipe, such that by only pressing the clamp against a pipe the at least one gripper attaches the clamp to the pipe.

2. The clamp according to claim 1 wherein the body of the clamp has the same radius of curvature as the pipe that it is attachable to, such that the clamp provides a tight fit when pressed against the pipe.

3. The clamp according to any of claims 1 to 2 wherein the clamp body comprises a section for spanning across a junction between two connected pipes.

4. The clamp according to any of claims 1 to 3 wherein the at least one gripper is arranged to grip to a collar surrounding the pipe.

5. The clamp according to any of claims 1 to 4 wherein the at least one gripper comprises one or more teeth for attaching the clamp to a pipe.

6. The clamp according to any of claims 1 to 5 wherein the at least one gripper is in the form of a mechanical press fit.

7. The clamp according to any of claims 1 to 6 wherein the at least one gripper is provided at an end of the clamp body.

8. The clamp according to any of claims 1 to 7 wherein the clamp is substantially elongate and there are at least first and second grippers, the first and second grippers being provided at the same end of the clamp and on opposite sides of the clamp.

9. The clamp according to claim 1 or 8 wherein the body comprises slits on either of the at least one gripper.

10. The clamp according to any of claims 1 to 9 when dependent on claim 3, wherein the clamp comprises at least one gripper at each end of the body, such that said section for spanning across a junction between two connected pipes is in between the at least one gripper provided at each end of the body.

11. The clamp according to any of according to any of claims 1 to 10 wherein the clamp is for clamping wires to a pipe.

12. The clamp according to claim 11 wherein the wires are control lines.

13. The clamp according to any of claims 1 to 12 wherein the clamp comprises one or more conduits for wires, the conduits being provided along the length of the clamp.

14. The clamp according to any of claims 1 to 13 wherein the clamp body is chamfered.

15. The clamp according to any of claims 1 to 14 wherein the clamp body comprises one or more holes for receiving one or more further attachment devices to the pipe.

16. The clamp according to any of claims 1 to 15 wherein the clamp comprises a lip for restricting axial movement of the clamp.

17. A collar for surrounding a pipe, the collar comprising: at least one clamp for attaching the collar to a pipe; and at least one groove on the exterior surface of the collar, such that a device is attachable to the collar by a gripper of the device engaging with the at least one groove when the device is only pressed onto the collar.

18. The collar according to claim 17 wherein the collar comprises a first and second portion in a male to female fit, wherein receiving the first portion into the second portion causes the at least one clamp to engage with the pipe such that the collar is attached to the pipe.

19. The collar according to any of claims 17 to 18 wherein a surface of the first portion is external to the male female fit, and said surface comprises the at least one groove.

20. The collar according to any of claims 17 to 19 wherein the at least one groove is on the exterior surface of the second portion.

21. The collar according to any of claims 17 to 20 wherein the collar comprises one or more identification marks for use in aligning the device for attachment with the collar.

22. The collar according to any of claims 17 to 21 wherein the collar comprises recesses on its exterior surface for providing further attachments to the collar than by the at least one groove.

23. The collar according to any of claims 17 to 22 wherein the device attachable to the collar is the clamp according to any of claims 1 to 16.

24. A pipe clamp system comprising: a collar attached to a pipe; and a clamp attached to the collar; wherein the attachment between the clamp and collar is achieved by only pressing the clamp against the collar.

25. The system according to claim 24, wherein the clamp is the clamp according to any of claims 1 to 16.

26. The system according to claim 24 or 25, wherein the collar is the collar according to any of claims 17 to 23.

27. The system according to any of claims 24 to 26 wherein the clamp comprises one or more conduits, for one or more wires, the conduits being provided along the length of the clamp, for spanning across a junction between two connected pipes.

28. The system according to any of claims 24 to 27 wherein the wire is a control line and the pipe is for use in the subsea oil industry.

29. A method of attaching a clamp to a pipe, the method comprising: pressing a clamp against a pipe so as to cause one or more grippers comprised by the clamp to engage into a gripping action, such that, by only pressing the clamp against the pipe, the clamp is held to the pipe.

30. The method of claim 29, further comprising the step of attaching a collar to the exterior of a pipe; wherein the pressing of the clamp against the pipe comprises pressing the clamp against the collar, wherein the one or more grippers of the collar engage one or more grooves of the collar.

31. The method according to any of claims 29 to 30 wherein the clamp is the clamp according to any of claims 1 to 16.

32. The method according to any of claims 29 to 31 wherein the collar is the collar according to any of claims 17 to 23.

33. The method according to any of claims 29 to 32 further comprising aligning the one or more grippers of the clamp and the one or more grooves of the collar prior to pressing the clamp against the collar.

34. The method according to claim 33, further comprising using a guiding mechanism to align the clamp and the collar such that the one or more grippers are aligned with the one or more grooves.

35. The method according to claim 34 wherein the guiding mechanism further comprises using an identification markon the collar.

36. The method according to any of claims 34 to 35 wherein the guiding mechanism further comprises using laser guiding to ensure the one or more grippers of the clamp are aligned with the one or more grooves of the collar.

37. The method according to any of claims 30 to 36 wherein the clamp is pressed to the exterior of the collar by a hydraulic press.

38. The method according to any of claims 30 to 37 further comprising providing further attachment means through holes in the clamp and receiving said attachment means in recesses on the collar.