GB2397090A

GB2397090A - Attachment securing to an elongate element

Info

Publication number: GB2397090A
Application number: GB0226927A
Authority: GB
Inventors: Peter Arthur Jordan
Original assignee: CHARLES TOMPKINS CONSULTANTS L
Current assignee: CHARLES TOMPKINS CONSULTANTS L
Priority date: 2002-11-19
Filing date: 2002-11-19
Publication date: 2004-07-14
Also published as: GB0226927D0

Abstract

An attachment, such as a floatation or weight element, for an elongate element, such as a wire rope or umbilical, comprises two moulded synthetic plastic material parts 1 and 2 hinged together. A catch 5 is pivotally mounted on one part 1 and helical springs 6 and 7 urges an end 9 of the catch into a complementary formation 10 in the other part 2. To attach a floatation element to an umbilical for example, the element is placed over the umbilical with the parts 1 and 2 separated and the parts squeezed together to allow the catch 5 to catch in the cutout 10. The element may be released by applying a force to counter the springs 6 and 7 and allow the catch 5 to withdraw from the cutout 10 and the pans 1 and 2 move apart.

Description

239',030

AN ATTACHMENT

The present invention relates to attachments for elongate elements. The attachment may be a floataton or weight element and the elongate element may be a wire rope or umbilical During offshore operations, attachments are frequently made to flexible elements that are over-boarded or recovered from the vessel to the sea Storage facilities such as winch drums rarely offer the option to wrap the flexible element with the attachment intact. In which case, the attachments are required to be added to and removed from the flexible element prior to leaving the vessel and storage respectively When floatation such as a buoy is attached or detached from an operational wire rope, there is always the risk of injury to the person performing the task as the rope may move unpredictably. This movement of the rope may be due to a number of factors such as the relative position between the two attached objects becoming suddenly shorter or longer or the severing of the wire rope due to excessive load It is an object of the invention to mitigate or eliminate these risks According to the present invention there is provided an attachment for attaching to an elongate element comprising two parts connected together which may be opened to allow introduction of the element between the parts and these closed about the introduced element and means for maintaining the parts in the closed position.

In a preferred embodiment of the invention each part is moulded from synthetic plastics material advantageously syntactic foam. Advantageously, each part comprises an internal formation to accommodate the elongate element. The parts are preferably hinged together on their sides remote from the means for maintaining The means for maintaining may comprise a catch pivotally mounted on one of the parts.

One end of the catch is formed to locate in an external formation in the other part and resilient means are constrained to act between the other end of the catch and the said one part. Advantageously, the resilient means comprises a spring, preferably a helical spring, which operates to urge the other end of the catch in to the external formation in the other part when the parts are in the closed position. Those parts of the moulded parts which are contacted by the catch are advantageously reinforced with metal.

In order that the invention may be more clearly understood, one embodiment thereof will now be described, by way of example, with reference to the accompanying drawings, in which.

Figure I is a plan view of an attachment in the form of a buoy, Figure 2 is a cross-section of the buoy taken along the line X-X in Figure 1, and Figure 3 is a cross-section of the buoy taken along the line Y-Y in Figure 2.

Referring to the drawings, the buoy comprises two parts 1 and 2 each moulded from synthetic plastics material, hinged together by means of a hinge pin 3 The material from which the parts l and 2 are moulded is chosen to withstand the hydrostatic pressure to which the buoy is subjected in use at depth The material may be Syntactic Foam. This is a moulded plastic material (for example polyurethane) with glass microspheres cast into it to help withstand distortion and reduction of volume (and hence buoyancy) when subjected to external pressure The two parts together define a through bore 4 to accommodate a wire rope, umbilical or other elongate element to which, in use, the buoy is attached. On their sides remote from the hinge pin 3, the parts I and 2 are shaped to accommodate a double catch 5. The catch 5 is mounted for pivotal movement about a pivot 20 mounted in the part 1. Two helical springs 6 and 7 are constrained to act between one end 8 of the catch and the part 1 The other end 9 of the catch is shaped to latch onto a metal reinforced cutout on the part 2. In the position shown, the catch holds the parts 1 and 2 together.

Pegs 11 moulded at the top of the part I serve to align the buoy in a mechanism (not shown) provided to fit the buoy on a cable or other elongate element Those areas of the parts I and 2 of the buoy contacted by the double catch 5 are locally reinforced with metal.

Buoys are stored in a container with the catches in the open position. To attach buoys to a cable or other elongate element, the buoys are released one at a time from the container either manually when required or automatically, for example, when a predetermined length of cable has passed After the buoy is placed over the cable a force is applied in the direction of the arrows FF to the two parts 1 and 2 to squeeze them together and allow the double catch 5 to close under the action of the springs 6 and 7 so that the end 9 of the catch latches in the cutout 10 If necessary to ensure latching a force may be applied to the end 9 of the catch 5 in the direction of arrow G. The forces in the directions of arrows F and G may then be removed leaving the buoy clamped on, the cable which may then be deployed into the sea. The pre-stress applied by the force in the directions of the arrows FF and the action of the springs 6 and 7 ensures that the buoy remains clamped on the cable even in deep water.

When the buoy is recovered onto a ship it is realigned with the release mechanism using the pegs 11 The catch on the buoy is opened by applying a force in the direction of arrow H on the end 8 of the double catch 5 against the force of the springs 6 and 7. This withdraws the end 9 of the double catch 5 from the metal reinforced cutout 10 allowing parts 1 and 2 to move apart. The force applied in the direction of arrow H may be applied by means of a pin running up a ramp 12 formed on the double catch 5 (see figure 3) or by other means.

It will be appreciated that the above embodiment has been described by way of example only and that many variations are possible without departing from the scope of the invention.

Claims

1. An attachment for attaching to an elongate element comprising two parts connected together which may be opened to allow introduction of the element between the parts and these closed about the introduced element and means for maintaining the parts in the closed position 2 An attachment as claimed in claim 1, in which each part is moulded from synthetic plastics material 3. An attachment as claimed in claim 1 or 2, in which each part comprises an internal formation to accommodate the elongate element 4. An attachment as claimed in claims 1, 2 or 3, in which the parts are preferably hinged together on their sides remote from the means for maintaining 5. An attachment as claimed in any preceding claim, in which the means for maintaining comprises a catch pivotally mounted on one of the parts 6 An attachment as claimed in claim 5, in which one end of the catch is formed to locate in an external formation in the other part 7. An attachment as claimed in claim 6, in which resilient means are contained to act between the other end of the catch and the said one part to urge the other end of the catch into the external formation in the other part when the parts are in the closed position 8. An attachment as claimed in claim 7, in which the resilient means comprises a spring 9. An attachment as claimed in claim 8, in which the spring is a helical spring An attachment as claimed in any of claims 5 to 9, in which those portions of the parts which are contracted by the catch are advantageously reinforced with metal.

An attachment substantially as hereinbefore described with referenced to the accompanying drawings.