SYSTEM FOR ATTACHING SUBSEA EQUIPMENT TO A LINE

Abstract

A system (100) for attaching devices of subsea equipment to a line (10) comprising a line holding mechanism (11,110) and a line holding unit (404). The line holding unit (404) comprises a 5 longitudinal slit (403) for receiving the line (10), multiple gripping elements (13,130,230), and at least one resilient element (12,120,220), related to one subsea device. The resilient element(s) is/are configured to force the multiple gripping elements (13; 130,230) in a direction towards the line (10), whereby the line holding unit (404) is locked to the line (10) in a locking position. By the invention an improved latching device and an accompanying system for attaching and 10 detaching subsea equipment to and from a line is obtained.

Claims

1-10. (canceled)

11. A system for attaching devices of subsea equipment to a line comprising: a line holding mechanism; and a line holding unit comprising a longitudinal slit for receiving the line, wherein the line holding unit comprises a plurality of gripping elements, and at least one resilient element, related to one subsea device, said at least one resilient element is configured to force the plurality of gripping elements in a direction towards the line, and wherein the line holding unit is locked to the line in a locking position.

12. The system according to claim 11, wherein the at least one resilient element is a spring device such as a leaf spring, a spring wire or a compressible device providing a force F towards the plurality of gripping elements.

13. The system according to claim 11, wherein the at least one gripping element comprises a hinge and each of the plurality of resilient elements holds a portion of the at least one gripping element closer to the line than the hinge when the line holding unit is locked to the line in the locking position.

14. The system according to claim 11, wherein each resilient element is arranged about the line holding mechanism, and adapted to move from an open positionwherein the resilient element(s) does(do) not move the gripping element in a direction towards the line,to the locking position, wherein the resilient element(s) is/are adapted to press in a direction towards the line whereby the line holding unit is locked to the line.

15. The system according to claim 11, wherein each line holding unit comprises at least two gripping elements, and at least one resilient element related to one subsea device, said gripping elements are arranged in the longitudinal direction of the line holding mechanism at the same side of the line and placed close to and on either side of the line holding mechanism related to same subsea device.

16. The system according to claim 11, wherein each gripping element is influenced by at least one resilient element, said each resilient element acting on one gripping element is providing a force in the direction towards the line independent of the other resilient elements acting on other gripping elements, and each resilient element is configured to force the gripping element in question in the direction towards the line, whereby the line holding unit is locked in the locking position by each gripping element independent of the other gripping element(s).

17. The system according to claim 11, wherein the line holding mechanism comprises an enlarged diameter compared with the diameter of the line providing a cylindrical thickening of the line.

18. The system according to claim 11, wherein the line holding mechanism is made from a resilient material, the gripping elements are serrated surfaces and the line holding mechanism comprises a guiding face for opening the longitudinal slit.

19. The system according to claim 11, wherein it further comprises a rotating device such as a wheel, or at non-rotating smooth and slippery device, said device is configured to push and/or assist the line into the longitudinal slit during deployment.

20. The system according to claim 11, wherein it further comprises a connection, said connection is placed between a housing for enclosing devices for subsea equipment and the line holding unit, or the connection is placed directly between a line holding unit and subsea equipment.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The invention will be explained with reference to exemplary embodiments and the accompanying drawings, in which:

[0043] FIG. 1A illustrates a first embodiment of a system according to the invention in a closed state.

[0044] FIG. 2A illustrates the first embodiment of a system according to the invention in an open state.

[0045] FIG. 1B illustrates a second embodiment of a system according to the invention in a closed state FIG. 2B illustrates the second embodiment of a system according to the invention in an open state.

[0046] FIG. 3 illustrates a third embodiment of the system according to the invention in a closed state.

[0047] FIG. 4 illustrates a system and the third embodiment of the system according to the invention in an open state.

[0048] FIG. 5 is a side view of the system in FIG. 4.

[0049] FIG. 6A illustrates a fourth embodiment of the system according to the invention and in a closed state.

[0050] FIG. 6B illustrates an enlarged and sectional view of the fourth embodiment of the system according to the invention shown in FIG. 6A.

[0051] FIG. 6C shows a perspective view of a C-shaped opening placed in a line holding unit.

[0052] FIG. 6D shows an enlarged view of a line comprising a line holding mechanism used in the embodiments shown in FIG. 6A,B and in FIG. 1A,B, 2A,B.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

[0053] The drawings are schematic and not to scale. Numerous details known to the skilled person are omitted from the drawings and the following detailed description.

[0054] FIG. 1A illustrates a line 10 and a first embodiment of a system 100 in a closed state. The system 100 comprises a line holding mechanism 11 and a line holding unit 404. The line holding unit 404made in an appropriate material such as metal or reinforced plastic materialincludes in this case one resilient element 12 acting on two gripping elements 13 placed on the same side of the line and at each end 11a,11b of the line holding mechanism 1. The resilient element 12 exert a spring force F on several gripping elements 13 in this case two gripping elements. Each gripping element 13 has a hinge 14, here at the apex of an isosceles triangle. A portion 15 of each triangle is closer to the line 10 than its hinged apex. The gripping element 13 could also be a longitudinal element hinged in one end and the other end resting against or placed close to an end of the line holding mechanism 11 when the system is in its locked position. The gripping elements 13 are in the locking position in FIG. 1A; an open position of the gripping elements is shown in FIG. 2A. The construction of the line holding mechanism 11 is explained below.

[0055] FIG. 2A shows the system 100 in an open state. The line 10 is visible in a longitudinal slit as necessary for entering and removing the line holding mechanism 11 from the line holding unit 404. FIG. 2A also depicts a housing 200 for seismic equipment. The housing 200 and the line holding unit 404 are affixed to each other and can be turned freely around the line 10 and line holding mechanism 11.

[0056] The line holding mechanism 11 is in this embodiment a sleeve crimped on the line 10 or it may be an element welded, moulded, bolted on the wire or otherwise fastened. The line holding mechanism 11 may also be constructed during the manufacturing of the line thereby making it an integrated part of the line 10. The line holding mechanism 11 is a cylindrical piece and permanently or semi-permanently attached to or integrated with the line 10. It may be removed by drilling or other mechanical means. It is mounted on the line 10 so it is motionless in relation to this during the use of the system 100. The length of the sleeve is a little shorter than the distance between the gripping elements 13. The diameter of the sleeve is larger than the diameter of the line 10 and is designed and dimensioned in such a way that the two end sections 11a,11b of the sleeve 11 makes a mechanical stop for the gripping elements. Thereby the line holding unit 404 is fastened to the line and thereby the seismic equipment attached to the line holding unit 404 is fastened/locked to the line 10.

[0057] A connection 210 between the line holding unit 404 and the housing 200 preferably contains a shock absorber for reducing the inertial forces applied to the subsea equipment during deployment. The connection 210 may also be directly between the line holding unit 404 and subsea equipment.

[0058] FIG. 1B and FIG. 2B show a second embodiment of the system 100 according to the invention. The difference between FIG. 1A, FIG. 2A and FIG. 1B, FIG. 2B is the number of gripping elements 13 and the number of resilient elements 12. In FIG. 1B and FIG. 2B the line holding unit 404 comprises 4 gripping elements 13. They are placed on either side of the line 10. Further, they are placed on either side of the line holding mechanism 11 as is the case with embodiment first.

[0059] One of the resilient elements 12 is acting on the two gripping elements 13 placed at one side of the line 10 and the other resilient element 12 is placed opposite the first resilient element 12 and acting on the two other gripping elements 13. By this arrangement, the locking of the line holding unit 404 to the line is made more secure.

[0060] FIG. 3 illustrates a third embodiment of the line holding mechanism 110 in a closed state. Here, the line holding mechanism 110 is made from a resilient material, e.g. rubber, which provides a kind of spring 120 and the spring force F exerted on the line 10. The gripping elements 130 are serrated surfaces and the line holding mechanism 110 comprises a guiding face 111 for opening the longitudinal slit.

[0061] FIG. 4 illustrates a system 100 comprising an opener 401 arranged to slide along the guiding face 111, which is shown as a straight line in FIG. 4. This causes an elastic deformation in the line holding mechanism 110 and opens the longitudinal slit for insertion or removal of the line 10. Wheels 402 pushes the line 10 into the longitudinal slit.

[0062] FIG. 5 is a side view of the system 100 in FIG. 4. The opener 401 is partially hidden behind the wheels 402, and both are hidden behind a side of the line holding mechanism 110.

[0063] FIG. 6A illustrates a fourth embodiment of the system 100. It shows the system 100 according to the invention and in a closed state comprising two separate pairs of gripping elements 230 working independent of each other. FIG. 6B illustrates an enlarged and sectional view of a part of the system 100 shown in FIG. 6A.

[0064] The system 100 comprises the line holding mechanism (not shown), two pairs of independent gripping elements 230 and two pairs ofindependent of each otherresilient elements 220, each configured as a straight spring wire. Each resilient element is acting independently of other resilient elements on one of the gripping elements 230. The gripping elements are placed in the same way, as is the case in FIG. 1B and FIG. 2B. That is each pair is placed at the same side of the line and linearly opposing, and the two pairs are placed opposite each other at each side of the line. The figure shows a cross-section view showing the spring 230 inside a hole through both the gripping element 230 and the line holding unit, held in place at each end by a setscrew 300. The head of a main bolt 215 holding the gripping element 230 has a cut-out 216 in its head to accommodate for the spring 220. As the gripping element 230 pivots around the bolt 215 providing a hinge 214, the spring 220 will bend. Each resilient element is acting on only one gripping element so the number of resilient elements and gripping elements are equal.

[0065] The gripping elements 230 is moved towards the linenot shownreaching the locked position, preventing the line from sliding through the housing. The line holding mechanism is constructed exactly as explained with reference to FIGS. 1A,B and 2A,B, the line holding mechanism comprising a sleeve placed around the line in the section that has to be locked. If one gripping element 230 is failing, the other gripping element 230 will take over the entire locking of the line. In this embodiment, two pairs of gripping elements 230 are shown. However, the system may comprise even less or more pairs of gripping elements 230 such as 3 or 4 or 5 or more. In that case, the same number of pairs of resilient elements 220 are provided: 3 or 4 or 5 or more.

[0066] FIG. 6C shows a perspective view of the line holding unit 404 comprising the longitudinal slit 403 designed as a C-shaped opening. The line holding mechanism 404 goes into the opening when constructed as a sleeve. A housing 200 attached to the line holding unit 404 encloses a part of the seismic equipment 400, which this housing 200 is designed to hold. The seismic equipment 400 may for instance be a seismic node, an acoustic transponder or other subsea equipment.

[0067] FIG. 6D shows an enlarged view of a line 10 comprising a line holding mechanism 11 designed as described with reference to FIG. 6A,B and FIG. 1A,B, 2A,B. The gripping elements 13,230 are engaging the line holding mechanism 11, as they are placed symmetrical around the line 10 on either side of the line 10 and further on either side of the line holding mechanism 11. The number of gripping elements here are 4, and the number of resilient elements is 4. If the gripping elements was two and placed as disclosed in FIG. 1A and FIG. 2A the number of resilient elements would be two, each acting on one gripping element and independent of the other resilient element.

[0068] The invention has been described by way of examples. The scope of the invention is defined in the appended claims.