GB2281318A

GB2281318A - Rope end terminations

Info

Publication number: GB2281318A
Application number: GB9317810A
Authority: GB
Inventors: Brian Malcolm Short
Original assignee: Bridon PLC
Current assignee: Bridon PLC
Priority date: 1993-08-27
Filing date: 1993-08-27
Publication date: 1995-03-01
Anticipated expiration: 2013-08-27
Also published as: NO943083D0; GB2281318B; NO311314B1; BR9402795A; NO943083L; GB9317810D0

Abstract

The termination of a rope, or a bundle of ropes, comprises a housing with a frusto-conical bore accommodating hollow members which wedgedly retain a rope end portion or rope ends. Spherical housing 12, Fig. 1, accommodates members 16 in which rope ends of a rope bundle are wedged by wedges 18. In Fig. 4, the members 16 are coaxial and retain wedged between their respective fibre layers of a single rope. <IMAGE>

Description

A ROPE END TERMINATION DEVICE The present invention relates to a rope end termination device.

Rope end termination devices of the type consisting of a socket, at least part of the inner wall of which is tapered, and a conically shaped member which fits within the socket to wedgedly retain rope end filaments in a space between the conically shaped member and the tapered inner wall are disclosed in United Kingdom patent no. 1341013 and United Kingdom patent publication no. 2236546A. Rope end termination devices of this type (hereinafter referred to as rope end termination devices of the type aforesaid) are primarily provided for terminating fibre ropes, particularly of the braided filament type.

Fibre ropes are increasingly being employed in deep water applications because of their good strength characteristics, and better weight to length ratio than steel ropes. In deep water applications such as the mooring of a petroleum production platform, for example, ropes having a diameter up to 250 millimetres and a length up to 2000 metres are required. A fibre rope having a diameter of 250 millimetres has a relatively large weight to length ratio. A rope of this diameter can only be provided in such lengths if manufactured at the point of use, which in deep water environments is impracticable. Alternatively, it is possible to transport to the point of use a number of shorter lengths of rope of the required diameter to be connected end to end to provide the desired length.

However, problems are encountered in terminating the ends of adjacent sections of rope for connecting together.

The dimensions of a rope end termination device of the type aforesaid are generally dictated by the diameter of the rope to be terminated. For example, for a 50 mm diameter rope, the length of a termination device socket would typically be 400 mm and the length of a conically shaped member for insertion in the socket would typically be 190 mm. Terminating a rope end using such a device is normally a manual task. It will be readily appreciated therefore that this task becomes increasingly physically difficult for ropes having diameters considerably greater than 50 mm. In deep water applications where ropes having a diameter upto 250 mm are required, a rope end termination device of the type aforesaid for terminating such a rope would be so large as to render it physically impossible to manually terminate the rope with said device.

An object of the present invention is to obviate and mitigate the aforesaid disadvantages.

According to one aspect of the present invention there is provided a rope end termination device comprising a housing member formed with a generally frusto-conical bore therethrough, within which a plurality of generally frusto-conical hollow members are located for receiving rope ends or rope end portions therein with the rope ends or rope end portions being wedgedly retained therein.

The frusto-conical hollow members may be located in juxtaposed relationship within said bore with a rope end or rope end portion being located and wedgedly retained within a respective one of each of such members.

Each of said rope ends or rope end portions may be wedgedly retained in a space between a generally conically shaped member located within a respective hollow member and a tapered inner wall of said member.

The included angle of each of the frusto-conical hollow members is preferably less than the included angle of the frusto-conical bore of the housing member.

Preferably, the included angles of the frustoconical members are equal, and may be such that when said members are arranged in juxtaposed relationship within the bore of the housing member, each of the members in contact with an inner wall of the bore contact said inner wall along a line of contact extending over a substantial portion of their length.

The frusto-conical hollow members may alternatively be located coaxially with separate rope end portions being located and wedgedly retained between adjacent pairs of such members.

The included angle of each of the hollow members may be equal to that of the bore of the housing member.

An external surface of the housing member may be shaped so as to be locatable within a fixture means, for example a seabed anchorage or mooring station.

Preferably, the external surface of the housing member generally defines a sphere.

Alternatively, the housing member may include fixture means for attachment to a fixture.

The housing member may include at one end thereof means to enable a housing cap member including fixture means to be affixed thereto.

According to a second aspect of the present invention there is provided a method of terminating a rope or bundle of ropes comprising: passing said rope or bundle of ropes through a generally frusto-conical bore of a housing member; positioning about the end of each rope end portion or rope end a generally frustoconical hollow member and inserting into said hollow member a generally conically shaped member to wedgedly retain said rope end portion or rope end in said hollow member; and withdrawing said rope or bundle of ropes through said bore in order to locate said hollow members terminating said rope end portions or rope ends in juxtaposed relationship within the bore of said housing member.

According to a third aspect of the present invention there is provided a method of terminating an end of a rope comprising: passing the end of the rope through a generally frusto-conical bore of a housing member; distributing the fibres of different layers of said rope end about respective frusto-conical members arranged generally coaxically; and drawing said rope back through the bore of the housing member in order to locate said coaxically arranged frusto-conical members within the bore of the housing member to wedgedly retain the respective rope end portions therebetween.

According to a fourth aspect of the present invention there is provided a rope or bundle of ropes terminated in accordance with the method of the second preceding paragraph.

According to a fifth aspect of the present invention there is provided a rope terminated in accordance with the method of the second preceding paragraph.

According to a sixth aspect of the present invention there is provided an intermediate connector device for a rope and/or a bundle of ropes comprising two housing members including means for securing said members together in back to back relationship, wherein each housing member is formed with a generally frustoconical bore therethrough, within which a plurality of frusto-conical hollow members can be located for receiving rope ends or rope end portions therein with the rope ends or rope end portions being wedgedly retained therein.

The frusto-conical hollow members may be located in juxtaposed relationship within the bores of the housing members.

Alternatively, the frusto-conical members may be arranged coaxically within the bores of the housing members.

The foregoing further features of the present invention will be more readily understood from the following description of preferred embodiments thereof with reference to the accompanying drawings, of which: Figure 1 is a cross-sectional view of a first embodiment of a rope end termination device according to the present invention; Figure 2 is a side-elevational view of a second embodiment of a rope end termination device according to the present invention; Figure 3 is a cross-sectional view of a housing member of the rope end termination of Figure 2; and Figure 4 is a side-elevational cross-sectional view of a third embodiment of a rope end termination device according to the present invention.

Referring to the drawings, Figure 1 shows a crosssectional view of a first embodiment of a rope end termination device 10 according to the present invention.

The device comprises a generally spherically shaped housing member 12 with a generally frusto-conical bore 14 therethrough. Inserted in juxtaposed relationship within the zore 14 are a number of generally frustoconical hollow members 16 which, in use, terminate respective ends of ropes of a bundle of ropes terminated by the device 10.

Each frusto-conical hollow member 16 has a conically shaped wedge member 18 associated therewith.

Each wedge member 18 fits within the hollow of its respective frusto-conical hollow member 16 to wedgedly retain filaments of a rope end in a space between the wedge member and an inner wall 20 of the hollow member 16 in a like manner to the rope end connecters described in United Kingdom patent no. 1641013 and United Kingdom patent publication no. 2236546A.

The included angle of each of the hollow members 16 is less than the included angle of the housing member bore 14. The included angles of the hollow members are preferably equal and are chosen such that the hollow members 16 fit tightly within the bore 14 of the housing member 12 when arranged in juxtaposed relationship therein. In this embodiment it can be seen that the hollow members 16 have a length substantially equal to the length of the bore 14 of the housing member. It will be understood, however, that the hollow members 16 can have any suitable length dependent on factors such as rope diameter, load etc.

The ropes terminated by the hollow member/conically shaped member combinations extend away from the termination device 10 exiting said device via an aperture 22 being the narrower of two apertures (22, 24) defining the limits of the bore 14 extending through the housing member 12.

In use, load exerted on the ropes of the bundle terminated by the device 10 causes further compression of the hollow members 16 within the bore 14 of the housing member 12 thereby increasing the grip exerted on the terminated rope ends.

The housing member 12, hollow members 16 and wedge members 18 can be made of any suitable material dependent on the environment in which the termination device 10 is intended to be employed.

The rope end termination device 10 is primarily intended to be used to terminate a bundle of ropes which can be utilised in replacement of a single rope of greater diameter than any of the ropes forming the bundle. In this way, the problem of terminating a single large diameter rope can be avoided since each rope of the bundle can be separately manually terminated using a hollow member/conical member combination prior to the terminated rope end with its associated hollow member 16 being arranged in position in the bore of the housing member 12. The device 10 can be utilised to terminate a single rope comprising a number of parallel strands wherein each strand end is wedgedly retained in a hollow member 16 thereby still achieving in part the object of the invention.

When terminating a bundle of ropes, the ends of the ropes are passed through the bore 14 of the housing member 12 via the narrow aperture 22. Each rope end is terminated as previously described. The ropes are then withdrawn back through the bore 14 in order to locate the hollow members 16 within the bore. This can be manually achieved.

A typical bundle of ropes might comprise seven ropes each of approximately 96 mm in diameter. The bundle so formed would be generally equivalent to a single rope having a diameter in the order of 250 mm.

The bundle of ropes may be loosely bound by an outer tubular jacket such as a polyester braided jacket to prevent entanglement.

A rope having a diameter of 250 mm can only be transported in relatively short lengths due to size limitations of the bobbin upon which the rope is wound and the weight of the bobbin and rope combination. For deep water applications requiring a large diameter rope or its equivalent, a problem is encountered in providing long lengths of sufficient diameter rope.

With large diameter ropes it is necessary to construct a desired rope length from a number of sections placed in end to end relation with ends of adjacent sections joined by connection devices.

The present invention overcomes the above problems by allowing a long length bundle of narrow diameter ropes to be formed which can be utilised in replacement of a larger diameter rope but which does not require intermediate connection devices. Also, the problem of transporting said lengths of narrower diameter rope are not as acute as for a large diameter rope since the lengths can be separately transported.

The exterior of the housing member is shaped to be locatable in a fixture means. This is of particular use in deep water applications where remote means can be used to cause engagement of the termination device with a fixture means, for example attaching a mooring tether line terminated by the device to an anchorage or mooring station. The exterior of the housing may be any suitable shape for locating within a fixture means although in this embodiment the housing is generally spherical.

In a second embodiment of the termination device 10 according to the invention as depicted in Figures 2 and 3, the device 10 includes a housing member 12 and housing cap member 26 bolted thereto by means of bolting through complementary flanges 28. The housing cap member 26 has a lug extending therefrom with an aperture 32 therethrough to allow the device to be shackled to a fixture.

It can be seen that two housing members 12 according to this embodiment could be secured together in back to back relationship by means of their flanges 28 to form an intermediary connection device for forming an even longer length bundle of ropes than that proposed.

A third embodiment of the termination device 10 of the present invention depicted in Figure 4 is of generally similar construction to that of the second embodiment (like numerals are used to denote like parts.) This embodiment of the device 10 differs from the second embodiment in so far that the frusto-conical hollow members 16 are arranged coaxically within the bore 14 of the housing member 12.This embodiment of the device 10 is primarily intended for termination of a single rope comprising a number of filament layers respective filament layers are arranged around Respective hollow members 16 to be wedgedly retained between an adjacent pair of suc ; members. In the present embodiment it will be seen that a rope comprising three filament layers could be terminated with a first outer layer of the rope (not shown) being wedgedly retained in a space between an inner wall 34 of the housing member 12 and a first hollow member 16a; a second inner filament layer being wedgedly retained in a space between said first hollow member 16a and a second hollow member 16b; and a third innermost filament layer being wedgely retained between said second hollow member 16b and a third frusto-conical member 16c. The third member 16c need not be hollow and is preferably solid in order that it may act as an urging member when the housing cap member 26 is secured to the housing member 12.

The frusto-conical members 16 (a, b, c), when arranged coaxically with rope filament layers arranged therebetween, extend beyond the bore 14 of the housing 12. When the housing cap member 26 is bolted to the housing member 12, it contacts with said third member 16c urging it into the bore 14 causing compression of the members 16 (a, b, c) toward the housing member 12 increasing the grip exerted on the rope layers. It will be understood that when terminating a rope using this embodiment of the device, it is preferable to firstly arrange the filaments of the innermost layer of the rope around the uppermost frusto-conical member 16c followed by the second and successive rope layers around respective frusto-conical hollow members.

It will be understood that the housing member of the various embodiments of the present invention will generally be substantial in size to allow termination of large diameter ropes or equivalent bundles of ropes.

However, the provision of frusto-conical members which locate within the bore of the housing and wedgedly retain rope end portions or rope ends therein allows, in the main, manual termination of the rope end portions or rope ends although it will normally be necessary for the housing member to be mechanically positioned.

Claims

1. A rope end termination device comprising a housing member formed with a generally frustoconical bore therethrough, within which a plurality of generally frusto-conical hollow members are located for receiving rope ends or rope end portions therein with the rope ends or rope end portions being wedgedly retained therein.

2. A rope end termination device as claimed in claim 1, wherein the frusto-conical hollow members are located in juxtaposed relationship within the bore of the housing with a rope end or rope end portion being located and wedgedly retained within a respective one of each of such members.

3. A rope end termination device as claimed in claim 1 or claim 2, wherein each of said rope ends or rope end portions is wedgedly retained in a space between a generally conically shaped member located within a respective hollow member and a tapered inner wall of said member.

4. A rope end termination device as claimed in any preceding claim, wherein the included angle of each of the frusto-conical hollow members is less than the included angle of the frusto-conical bore of the housing member.

5. A rope end termination device as claimed in claim 4, wherein the included angles of the frusto-conical members are such that when said members are arranged in juxtaposed relationship within the bore of the housing member, each of the members in contact with an inner wall of the bore contact said inner wall along a line of contact extending over a substantial portion of their length.

6. A rope end termination device as claimed in claim 1, wherein the frusto-conical hollow members are located coaxially with separate rope end portions being located and wedgedly retained between adjacent pairs of such members.

7. A rope end termination device as claimed in claim 6, wherein the included angle of each of the hollow members is equal to that of the bore of the housing member.

8. A rope end termination device as claimed in any preceding claim, wherein an external surface of the housing member may be shaped so as to be locatable within a fixture means, for example a seabed anchorage or mooring station.

9. A rope end termination device as claimed in claim 8, wherein the external surface of the housing member generally defines a sphere.

10. A rope end termination device as claimed in any preceding claim, wherein the housing member includes fixture means for attachment to a fixture.

11. A rope end termination device as claimed in claim 10, wherein the housing member includes at one end thereof means to enable a housing cap member including fixture means to be affixed thereto.

12. A method of terminating a rope or bundle of ropes comprising: passing said rope or bundle of ropes through a generally frusto-conical bore of a housing member; positioning about the end of each rope end portion or rope end a generally frustoconical hollow member and inserting into said hollow member a generally conically shaped member to wedgedly retain said rope end portion or rope end in said hollow member; and withdrawing said rope or bundle of ropes through said bore in order to locate said hollow members terminating said rope end portions or rope ends in juxtaposed relationship within the bore of said housing member.

13. A method of terminating an end of a rope comprising: passing the end of the rope through a generally frusto-conical bore of a housing member; distributing the fibres of different layers of said rope end about respective frusto-conical members arranged generally coaxically; and drawing said rope back through the bore of the housing member in order to locate said coaxically arranged frusto-conical members within the bore of the housing member to wedgedly retain the respective rope end portions therebetween.

14. A rope or bundle of ropes terminated in accordance with the method of claim 12.

15. A rope terminated in accordance with the method of claim 13.

16. An intermediate connector device for a rope and/or a bundle of ropes comprising two housing members including means for securing said members together in back to back relationship, wherein each housing member is formed with a generally frustoconical bore therethrough, within which a plurality of frusto-conical hollow members can be located for receiving rope ends or rope end portions therein with the rope ends or rope end portions being wedgedly retained therein.

17. An intermediate connector device as claimed in claim 16, wherein the frusto-conical hollow members are located in juxtaposed relationship within the bores of the housing members.

18. An intermediate connector device as claimed in claim 16, wherein the frusto-conical members are arranged coaxically within the bores of the housing members.

19. A rope end termination device substantially as hereinbefore described with reference to fig. 1 of the drawings.

20. A rope end termination device substantially as hereinbefore described with reference to figs. 2 and 3 of the drawings.

21. A rope end termination device substantially as hereinbefore described with reference to fig. 4 of the drawings.

22. A method substantially as hereinbefore described with reference to figs. 1 to 3 of the drawings.

23. A method substantially as hereinbefore described with reference to fig. 4 of the drawings.

24. A rope or bundle of ropes terminated in a manner substantially as hereinbefore described with reference to figs. 1 to 3 of the drawings.

25. A rope or bundle of ropes terminated in a manner substantially as hereinbefore described with reference to fig. 4 of the drawings.