WO2013081465A1

WO2013081465A1 - Sliding wedge cleat for a large diameter fibre rope

Info

Publication number: WO2013081465A1
Application number: PCT/NO2011/000316
Authority: WO
Inventors: Harald Kåre STAURNES
Original assignee: Triplex As
Priority date: 2011-11-08
Filing date: 2011-11-08
Publication date: 2013-06-06

Abstract

A fibre rope lock (1 ) with a base frame (D, H) provided with two oppositely arranged jamming cleats (C) arranged each on its sliding wedge surface (A1 ) in said base frame (D, H), wherein said jamming cleats (C) are provided each with its across directed slide rail (K2) provided with a friction plate (B) below and between said jamming cleats (C) and arranged for being pulled along with said rope (T) in its running direction for at least locking said jamming cleats (C).

Description

SLIDING WEDGE CLEAT FOR A LARGE DIAMETER FIBRE ROPE

Introduction

The invention is a cleat for fiber rope, for handling and locking of synthetic fiber rope of large dimensions, comprising two jamming cleats and a friction plate arranged in a base frame with a wedge- shaped opening.

The purpose of the invention is for it to be used to solve a problem related to hold on to or stop undesired release of a fiber rope in a simple manner and secure way. The need is particularly within the marine industry such as for anchor handling vessels offshore and service vessels for the aquaculture while there is at need to hold one end of the rope during splicing in a new length of rope or during maintenance or during work with and around a connection device . The sliding wedge cleat may be used for different dimensions of fiber ropes. A fiber rope for anchor handling is typically of a very large diameter: 0 160 - 210 mm and even up to 300 mm.

A required clamping force is assumed to be 20 tons.

Prior art

The market has over long time requested simple and secure mechanisms as solutions for locking and holding on to thick fiber ropes. The method used today comprises the use of straps, in that a chain or another rope is secured around the fiber rope and attached to a winch or another fixed point.

Suppliers of fiber ropes specify that a clamping force onto the rope may be equivalent to the pulling load on the rope without damaging the fibers and consequently damaging the rope.

GB1438932 describes a wedge shaped jamming cleat with resilient springs which control the jaws into locked position and tighten them. The locking mechanism is intended for shorter adjustment grip for a rope e.g. by hauling in a sail. The spring mechanism is not intended to handle ropes of large diameters and high pulling forces in the order of tens of tons .

DE2114569 concerns a wedge cleat in a wedge frame with two jagged jamming cleats which hold the line by using the principle of using a jamming wedge. The rope needs to be in contact with the jamming cleats to start unlocking of the lock. A spring may help holding the jamming cleat in locked position. The wedge cleat is arranged for manual holding of lines and ropes, e.g. at a sailing boat. US3758922 shows a sliding wedge cleat with jagged gripping surfaces and a spring tensioner to press the lock into a locked position, but allows it to open for inserting a rope into the slot between the jamming cleats, in that the jamming cleats may slide backwards and away from the rope against the slanting wall in the lock. The lock is designed for constituting a manually releasable holder for ropes onboard a yacht .

NO760641 comprises a hawser stopper with a housing arranged for rotating up about an axis parallel to the hawser. The housing is held closed around the hawser by a flap with a locking pawl and the house has jamming cleats and wedge plates arranged along aslant walls inside the housing. The hawser stopper is arranged with gusset plates and is anchored to the vessel deck by chains. In this way the hawser stopper lies unfixed on the deck and release of the hawser will be impossible if the hawser is loaded and may not be hauled in along the deck.

An anchor handling vessel for an anchor spread for an oil platform must be capable of handling anchor lines comprising gross chain with sections of synthetic fiber rope of very large diameter; 90 to 300 mm. A shark jaw may stop the chain at any place along the chain sections but is incapable of stopping a synthetic fiber rope other than at shackles or eyelets. At the same time it is important that if the shark jaw or a jamming cleat is holding the anchor line or a rope of large diameter in the sea, it must, in an emergency

situation, be capable of releasing the anchor line or the rope very quickly in order to prevent damages to the vessel or a marine casualty.

Short summary

The invention is a sliding wedge cleat (1) for fiber ropes

comprising a base frame (D, H) with two opposite cleats (C) arranged on each belonging sliding wedge plate (Al) in the base frame (D, H) wherein the cleats (C) each comprising a lateral placed slot (Kl) for a lateral arranged sliding track (K2) comprising a friction plate (B) under, and between the cleats (C) and arranged to be pulled along in the running direction of the rope (T) for at least locking the cleats (C) around the rope. In this way one may clamp thick fiber ropes in a secure way and the clamping force will increase accordingly to the pull load. In an embodiment of the invention the sliding wedge cleat (1) for fiber ropes comprise least two contact faces (Ul) to bear against the appurtenant upright jaw (U) in a shark jaw at a deck. Shark jaws like this are intended for locking of chains and/or wire but do not work well on fiber ropes. When the sliding wedge cleat operates in combination with a shark jaw one may handle fiber rope influenced by the same pull load as the chain that the shark jaw is dimensioned for with high security and reduced manual handling compared to locking of ropes by using extra wire, rope or chain.

Figure captions

Fig. 1 shows in a perspective view a sketch of an embodiment of the sliding wedge cleat according to the invention comprising a nose portion for being arranged in a shark jaw.

Fig. 2a and 2b is a frontal view of an embodiment of the invention, in open and locked positions respectively, with the rope (T) placed in the gap. Fig. 3 a and 3b show a top view of an embodiment of the invention, in open and locked positions respectively, with the rope (T) placed in the gap.

Fig. 4 shows in a perspective view, an embodiment of the invention wherein the sliding wedge cleat is in cooperation with a shark jaw and the rope is placed in the lock. In addition the chassis of the shark jaw under deck is shown.

Fig. 5 shows a front view of an embodiment as shown in Fig. 4.

Fig. 6 shows a top view of an embodiment as shown in Figs. 4 and 5 with a detail enlargement view showing the lock pads at the elongated nose section in a locked position.

Fig. 7 shows a sketch of the sliding wedge cleat arranged on the seaward side of the shark jaw.

Fig. 8 shows a shark jaw gripping on to a chain extending over the deck and out to the sea.

Embodiments of the invention

The invention is a sliding wedge cleat (1) for fiber ropes

comprising a base frame (D, H) with two opposite cleats (C) arranged on the corresponding sliding wedge surfaces (Al) in the base frame (D, H) wherein the cleats (C) each comprise a lateral placed slot (Kl) for a laterally directed sliding rail (K2) comprising a friction plate (B) under and between the cleats (C) and arranged to be pulled along in the running direction of the rope (T) for at least locking the cleats (C) around the rope. In this way one may clamp thick fiber ropes in a secure way and the clamping force onto the rope will increase depending of the pull load at the rope.

The friction plate provides for that the rope by its own weight and pull force contributes to a quick locking of the rope. The invention comprises a base unit with cleats wherein the contact faces towards the center line (S) forms an angle with to the centerline, mounted on a base plate (D) . This angle depends on the friction coefficient between the fiber rope and the jamming cleats (C) . The angle cannot be wider than what may give "self blocking". The locking principle to the fiber rope itself is based on "wedge jamming principle". The fiber rope may freely be put into the sliding wedge cleat and pass between the two jamming cleats.

When the fiber rope lies on top of the friction plate (B) with sufficient weight and the rope is lowered in a controlled way controlled (unwound form the winch) , the jamming cleats (C) at the same time are pulled, by using guiding slots, perpendicularly to the tension direction of the rope forward, together with the friction plate, into the wedge shaped aperture in the base frame (H) . The length of the jamming cleats (C) are dimensioned in such way that the rope is not damaged due to the clamping force formed. To ensure good contact between the jamming cleats and the rope, one may manually, for instance by a rubber club, hammer on the reverse side of the jamming cleats (C) until the plates at both sides are brought in good contact with the fiber rope and thereby start pulling the jamming cleats into the wedge formed in the base frame (H) at an earlier stage. The clamping force of the locking mechanism which acts on the fiber rope when it is "jammed" is a result of the pulling force (load) at the pulling side of the locking mechanism.

In an embodiment of the invention the sliding wedge cleat comprises at least two contact surfaces (Ul) to bear against each

corresponding, upright jaw (U) , in a shark jaw at a deck. Shark jaws like this are designed as two jaws and are designed for locking off chains and/or wire or shackles but do not work well on fiber ropes. So-called shark jaws may have different geometrical designs. They may for instance be cylindrical or comprise one or more plate shaped sides. They may be arranged for being elevated from and lowered into a ship deck with for instance hydraulic rise/sink mechanisms or pivot functions. There are several types at the market, i.e. Rolls Royce (R) and Kari ay Winch(R) as well as Triplex shark jaw. When the sliding wedge cleat operates in combination with a shark jaw one may handle fiber rope, loaded by the same pull load as the chain for which the shark jaw is dimensioned, with a high degree of security and with reduced manual handling compared to locking off ropes by using extra wire, rope or chain. When mounted together with a

Triplex Shark Jaw the sliding wedge cleat is in an embodiment a complete fiber rope and chain stopper. As an example the retention capacity may be from 100 to 700 tons SWL (Safe Working Load) .

The base unit as shown, is made to fit into a Triplex Shark Jaw when the two jaws stand in a vertical position (shark jaw in operative and locked position) , and is thereby stopped, bears the jaws in a secure way wherein the jaws form a 90° angle.

The sliding wedge cleat according to an embodiment of the invention comprises in the base plate (D) a nose section (Dl) which extend out in the locking direction between the jaws (U) in the shark jaw. The base plate further comprises two pivotable dogs (E) arranged for holding the sliding wedge cleat (1) in the shark jaw if the fiber rope (T) is pulled against the locking direction. The sliding wedge cleat is thus locked in the shark jaw and the rope may, as distinct from the concepts in prior art, be retracted without the fiber lock following along back with the rope. The dogs may be of a

pivoting/snap lock mechanism arranged to hold the entire unit in place when one shall release the fiber rope, i.e. pull the cleats (C)and the fiber rope out rearwards and wind in onto the winch. In this case the cleats (C) are pulled outwardly, the friction plate (B) correspondingly rearwards, and the hold around the rope is released.

In an embodiment of the sliding wedge cleat according to the invention each jamming cleat (C) is arranged with a corresponding guiding fin (F) arranged for running in an corresponding

longitudinal guiding slot (F2) in an corresponding sliding wedge plate (Al) , and the cleats (C) are held in place in the base frame.

Those guiding fins (F) have in an embodiment of the invention athwart directed pins (Fl) arranged to run in a corresponding guiding slot (A2) parallel arranged to the corresponding sliding wedge surface (Al ) . When the rope is pulled back together with the cleats (C) clamping around the rope, the pins will slide in the guiding slots and the cleats (C) are by forced motion led away from the rope and release it . In an embodiment of the invention the guiding slots (A2) have a limited extension in a direction opposite to the locking direction to stop a pin (Fl) and in that way prevent a cleat (C) from slipping out of the base frame (D,H) , and by this the sliding wedge cleat is held integrally connected during a possible retraction of the of the rope. Preferably, both the cleats are provide with such a mechanism.

Additional guidance may, in an embodiment of the invention, be achieved in that the sliding wedge cleat is arranged with a

longitudinal guide track (K) in the base plate (D) for guiding a keel (Bl) arranged under the friction plate (B) . The friction plate (B) is guided by the guide track (K) in the center of the base plate (D) and is thus running back and forth at the plate parallel with the direction of the fiber rope. In an embodiment of the invention were the sliding wedge cleat is a free-standing unit for use together with other equipment, such as a shark jaw or another form of chain stopper, -guide or the like at deck, the base frame (D, H) comprises attachment lugs for attachment of chains, ropes and the like for handling by winch or crane on deck. The sliding wedge cleat weighs approximately 500 kg and may not be manually operated.

An embodiment of the sliding wedge cleat according to the invention is arranged for cooperating with a shark jaw wherein the jaws are tilted up of the deck level. The angle between the contact surfaces (Ul) are, in such an embodiment, equal to the angle between the raised jaws (U) of the shark jaw. With that, we achieve a robust sliding wedge cleat that may handle fiber ropes of a large diameter loaded by high load as for instance 20 tons. The invention, in an embodiment, may be arranged on top of a vertically directed piston. The top of the piston is arranged for being raised from the deck surface in order to bring the sliding wedge cleat (1) into intervention with the rope (T) from underneath. This is an advantageous embodiment for handling fiber rope that is not running close to the deck level and one may, in this way, not have to use other forces to press the rope down between the cleats in the sliding wedge cleat. Such an embodiment is preferred used in cooperation with a shark jaw wherein the jaws are assembled or closed above the rope so as the rope will not be pulled out of position but be held back and be guided into position in the sliding wedge cleat .

In an embodiment of the invention the sliding wedge cleat with the base frame (D, H) is sinked into the deck, arranged with an actuator and arranged for being elevated up into a working position to bring the sliding wedge cleat (1) into intervention with the rope (T) and to be lowered back down to become flush with the deck level. The actuator may be for example electrically or hydraulically

controlled. Such an embodiment provides for an unobstructed plane deck suitable for handling of other equipment, for instance a chain coupled to the rope. When the working operation requires locking off the fiber rope, the sliding wedge cleat may be raised up from the surface deck level into a working position. The sliding wedge cleat must in such an embodiment be arranged with sufficient connectors so as for handling heavy loads, for instance 20 ton. In an embodiment like this, the invention is a free-standing unit, arranged for being elevated or lowered and to be integrated in the ship deck that has no shark jaw, or has other equipment without a Triplex (R) designed shark jaw / chain stopper, or that it is arranged at the sea facing side related to the shark jaw.

When edges and corners may be in contact reach of the rope (T)the sliding wedge cleat is in an embodiment of the invention comprising rounded edges to prevent damages on the fiber rope during the jamming and locking operation. A major advantage by the present invention is that, when used in combination with the shark jaw, one may use the same equipment for hauling in of the total anchor line which may comprise en anchor winch chain, a wire line, a fiber rope and an anchor chain, all of very large dimensions. It will be easy to carry out a quick release of the rope from the remaining equipment, or to do a quick emergency release. In an embodiment of the invention a quick emergency release may be performed by lowering the jaws of the shark jaw stopper from an upraised position to a horizontal position "flat on deck", and thereby release the sliding wedge cleat from the fastening point at deck, and may follow along with the rope into the sea if a need for such an operation should occur. The same function for other types of chain stoppers will be achieved when lowering the cylindrical stopper down and under the deck. The manual operation of fixing by chain or rope is eliminated.

Claims

1. A sliding wedge cleat (1) for fiber ropes, comprising a base frame (D, H) with two opposite cleats (C) arranged on each

corresponding sliding wedge surface (Al) in the base frame (D, H) wherein the cleats (C) , each comprising a athwart directed slot (Kl) for a laterally directed slide rail (K2) provided with a friction plate (B) under and between the cleats (C) and arranged for being pulled along in the running direction of the rope (T) for at least locking the cleats (C) about the rope.

2. The sliding wedge cleat (1) for fiber ropes according to claim

1, wherein the base frame (D, H) is arranged with at least two contact faces (Ul) to rest against each its corresponding upright jaw (U) in a shark jaw.

3. The sliding wedge cleat (1) for fiber ropes according to claim

2, wherein the base plate (D) comprises a nose section (Dl) which extends in the locking direction between the jaws (U) in the shark jaw and arranged with two pivotable locking dogs (E) arranged for holding the sliding wedge cleat (1) in the shark jaw if the fiber rope (T) is pulled opposite the locking direction. 4. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims, wherein each jamming cleat (C) is provided with an appurtenant guiding fin (F) arranged for running in an appurtenant longitudinal guiding slot (F2) in the appurtenant sliding wedge plate (Al) . 5. The sliding wedge cleat (1) for fiber ropes according to claim

4. wherein the guiding fins (F) are arranged with an appurtenant athwart directed pin (Fl) for each guiding fin (F) , each arranged to run in an appurtenant guiding slot (A2) parallel to the appurtenant sliding wedge plate (Al) .

6. The sliding wedge cleat (1) for fiber ropes according to claim 5, wherein at least one of the guiding slots (A2) has a limited extension in the direction against the locking direction, for stopping a pin (Fl) .

7. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims, wherein the base plate (D) has a longitudinal guide track (K) to guide a keel (Bl) arranged under the friction plate (B) .

8. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims, wherein the base frame (D, H) is provided with attachment lugs for chains, ropes and the like, for handling on deck.

9. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims 2 to 8, wherein the angle between the contact faces (Ul) is equal to the angle between the upright jaws (U) of the shark jaw.

10. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims 2 to 9, wherein the base frame (D, H) are arranged on top of a vertically directed piston arranged for being elevated up from the deck's surface in order to bring the sliding wedge cleat (1) into intervention with the rope (T) from underneath.

11. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims, wherein the base frame (D, H) is sinked into the deck, arranged with an actuator and arranged for being elevated up in a working position to bring the sliding wedge cleat (1) into intervention with the rope (T) and to be lowered level with the deck surface.

12. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims, wherein edges and corners in contact reach of the rope (T) are arranged with rounded edges to prevent damage to the fiber rope during the jamming and locking operation.

13. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims, arranged for fiber ropes of diameter between 90 and 300 mm.

14. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims, wherein the rope facing contact faces of the cleats (C) are principally parallel.

15. The sliding wedge cleat (1) for fiber ropes according to any of the preceding claims, wherein the contact faces of the cleats (C) comprise a longitudinal groove for the rope (T) .