GB2531578A

GB2531578A - Latch Assembly

Info

Publication number: GB2531578A
Application number: GB1418838.7A
Authority: GB
Inventors: Conlon Gordon; Lavelle Paul; Macknocher Scott
Original assignee: ENNSUB Ltd
Current assignee: ENNSUB Ltd
Priority date: 2014-10-22
Filing date: 2014-10-22
Publication date: 2016-04-27
Anticipated expiration: 2034-10-22
Also published as: GB2531578B; GB201418838D0

Abstract

Apparatus 301 for attachment to a standard hydraulic A-frame (107 fig. 1) onboard a vessel (101 fig. 1) comprises a housing 302 which allows passage of an umbilical cable 106 or wire rope through a central region and which comprises two pivotable fingers 306 positioned in a directly opposing arrangement on the periphery of the housing 302, each of the pivotable fingers 306 being independently hydraulically driven to an open position by spring-loaded hoseless hydraulic cylinders 303 situated in a directly opposing arrangement on the periphery of the housing 302 perpendicularly to each pivotable finger 306, each pivotable finger 306 also being closed under spring-action, and, once closed, latching onto an umbilical termination socket 501 on the umbilical cable 106 or wire rope which passes through the housing 302, the housing 302 comprising first and second ports 308, 309 for receiving incoming and return hydraulic pressure hoses respectively and also a series of grooves 502, 503 and cross-drillings (902 fig. 9) to provide a direct hydraulic feed from the incoming hydraulic pressure hose to the hydraulic cylinders 303. The umbilical cable 106 or wire rope may be a load bearing steel armoured cable or rope for lowering a tether management system (103 fig. 1) and/or a remotely operated vehicle (104 fig. 1) from the vessel (101 fig. 1).

Description

Latch Assembly

CROSS REFERENCE TO RELATED APPLICATIONS

This application represents the first application for a patent directed towards the invention and the subject matter.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to apparatus which is configured for attachment to a standard hydraulic A-frame onboard a vessel for securing an umbilical cable or wire rope at a fixed position from the vessel. * * * * * * * * *

BRIEF SUMMARY OF THE INVENTION

According to an aspect of the present invention, there is provided apparatus configured for attachment to a standard hydraulic A-frame onboard a vessel comprising: a housing configured to allow passage of an umbilical cable or wire rope through a central region, said housing comprising two pivotable fingers positioned in a directly opposing arrangement on the periphery of said housing, wherein each said pivotable finger is independently hydraulically driven to a first open position by one of two spring-loaded hoseless hydraulic cylinders situated in a directly opposing arrangement on said periphery of said housing perpendicularly to each said pivotable finger and wherein each said pivotable finger is closed under spring-action to a second closed position, wherein each said pivotable finger in said second closed position is configured to latch onto an umbilical termination socket on said umbilical cable or wire rope passing through said housing, and further wherein said housing comprises a first port for receiving an incoming hydraulic pressure hose and a second port for receiving a return hydraulic pressure hose, and further wherein said housing comprises a series of grooves and cross-drillings to provide a direct hydraulic feed from said incoming hydraulic pressure hose to each said hydraulic cylinder. *:** * **

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a vessel containing apparatus for lowering a tether management system and remotely operated vehicle into the sea;

Figure 2 shows a latch assembly of the prior art;

Figure 3 shows a perspective view of the apparatus embodied in the present invention in a closed state; Figure 4 shows a perspective view of the apparatus embodied in the present invention in an open state; Figure 5 shows a cross section of the apparatus embodying the present invention in a closed state; Figure 6 shows a cross section of the apparatus embodying the present invention in an open state; Figure 7 shows a perspective view of a hoseless hydraulic cylinder embodied in the present invention; Figure 8 illustrates the apparatus embodied in the present invention; Figure 9 shows a cross sectional view of the cross-drillings embodied in the present invention; and Figure 10A shows a top view of the embodied apparatus and Figure 10B shows a simplified cross-sectional view of cross-drillings from the grooves to the cylinders.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS * * *

Figure 1 Vessel 101 containing winch 102 for lowering a tether management system 103 and remotely operated vehicle 104 into the sea to perform subsea tasks is illustrated in Figure 1. Submersible ROV 104 may be fitted with cameras, lights and manipulating devices to enable underwater investigations to be performed. ROVs are widely used in the offshore oil and **** gas industry, as well as in renewable energy projects, police work and civil engineering. Submersible ROV 104 is tethered to TMS 103 which pays tether 105 in and out when ROV 104 has reached its working depth. Tether **** 105 acts as a means to allow submersible ROV 104 to perform underwater investigations and explorations at a distance from TMS 103 and in any direction.

Umbilical cable 106 is used to lower TMS 103 and ROV 104 beneath the sea. Umbilical cable 106 may be up to 3000 metres long and is a load-bearing steel armoured cable containing electrical conductors and fibre io optics to allow power, video and data signals to be transmitted back and forth between submersible ROV 104 and TMS 103 and vessel 101. In an alternative embodiment, umbilical cable 106 may be a wire rope.

Winch 102 is bolted behind conventional A-frame 107 on vessel 101. Winch 102 is used for unwinding umbilical cable 106 when TMS 103 and ROV 104 are to be lowered into the sea and then winding up umbilical cable 106 when TMS 103 and ROV 104 are to be raised. Umbilical cable 106 thus moves up and down. When TMS 103 and ROV 104 are raised out of the sea they are docked onto A-frame 107. This is a safety measure to ensure both TMS 103 and ROV 104 are mechanically connected to A-frame 107 as they are brought onboard the vessel. This removes the need for winch 102 to maintain tension to hold TMS 103 and ROV 104.

TMS 103 and ROV 104 are mechanically connected or docked onto A-frame 107 by apparatus 108 embodied in the present invention. Umbilical cable 106 passes through apparatus 108, known as latch assembly 108 or docking box 108. Umbilical cable 106 possesses an umbilical termination socket, which may also be known as bullet (not shown in this Figure). The physical shape of the umbilical termination socket allows it to connect in to latch assembly 108. Failure of latch assembly 108, which may for example cause the umbilical termination socket to fall out of the latch assembly, may subsequently cause TMS 103 and ROV 104 to be dropped onto the sea bed. * * * . * * * * . . * * * * * * * * *

Latch assembly 108 is therefore a critical component of the standard hydraulic A-frame onboard a vessel.

Figure 2 A latch assembly or docking box of the prior art is shown in Figure 2.

There are, however, problems associated with latch assemblies of the prior art. Prior art latch assemblies comprise a fabricated carbon steel housing 201 which is then painted with offshore paint in order to prolong the life of the housing. It is very difficult to control the thickness of the paint layers, and uneven paint layers may undesirably interfere with the latch assembly function.

Prior art latch assemblies have at least two hydraulic hoses 202 which pass into the cylinder (not herein shown) of the latch assembly. The function of these hydraulic hoses is to provide hydraulic pressure to the cylinder to consequently open the pivotable latch fingers. However, these hydraulic hoses are vulnerable in their positioning, and as the cylinder moves, may become tangled, subject to failure and damage.

The two fingers of the prior art latch assemblies are configured to move together, namely when one moves, the other one also moves. The two fingers in the fabricated housing of a prior art latch assembly are connected on one side of the housing by a spring 203 which causes the two fingers to close together and are connected on the other side of the housing by a cylinder (not herein shown) which causes the two fingers to open together. Consequently, failure of the single cylinder or spring may cause a situation where both pivotable latch fingers cannot close and hence the socket cannot be held in the docking box. There is no built in redundancy to the system.

Finally, there may be sensors on prior art latch assemblies but these sensors are only capable of detecting whether the pivotable latch fingers are open or closed. These sensors do not make it possible to see exactly at which angle each pivotable latch finger is positioned. The sensors on prior art latch assemblies do not therefore provide any degree of accuracy with regards to the movement of the pivotable latch fingers.

The latch assembly embodied in the present invention overcomes all the problems associated with prior art latch assemblies.

* * * * ** * * * *7^iib * ** * * ***C o e* * * * * * * Figure 3 Figure 3 shows a perspective view of the apparatus 301 embodied in the present invention in a closed position. The apparatus 301 embodied in the present invention provides an improved latch assembly which can hold a safe working load (SWL) of 13.6 tonnes and provides an improved latch assembly which overcomes the problems associated with the prior art.

Apparatus 301 attaches to a standard A-frame onboard a vessel and comprises a CNC (computer numerical control) precision-machined stainless steel circular housing 302. In direct contrast to prior art latch assemblies which require painting with a suitable offshore paint, CNC precision-machined stainless steel circular housing 302 does not corrode and does not require painting. The problem associated with the prior art of uneven paint layers is therefore eliminated.

Apparatus 301 comprises two cylinders 303 positioned on directly opposite sides of the periphery of the housing 302. Only one of the two cylinders 303 can be seen in Figure 3. The two cylinder requirement of the present invention is in contrast to that of prior art latch assemblies which only have a single cylinder. Cylinders 303 are spring-loaded hoseless hydraulic cylinders. Cylinders 303 are directly bolted onto each side of housing 302 and in the illustrated embodiment, four bolts are used to attach each cylinder 303 to said housing 302.

Each cylinder 303 is connected to a link plate 304 which itself is attached to a pivot shaft 305. Only one of the two link plates 304 and one of the two pivot shafts 305 is shown in Figure 3. Pivot shaft 305 is directly connected to pivotable finger 306. Movement of cylinder 303 causes movement of link plate 304 which itself causes movement of the pivot shaft *** * 305. Movement of the pivot shaft 305 causes pivotable finger 306 to open and close. Pivotable finger 306 as illustrated in Figure 3 is in a closed position. In order to allow opening and closing of each pivotable finger 306, each of the two said cylinders 303, linking arms 304 and pivotable shafts 305 are oriented in an opposite direction to each other on the periphery of the housing 302.

The umbilical cable, or wire rope, (not herein shown) passes through the central region 307 of housing 302. When pivotable fingers 306 are in a closed position, the umbilical termination socket of the umbilical cable is grasped by pivotable fingers 306 (only one of which is illustrated in Figure 3) and the umbilical cable is secured at a fixed position. This thus enables the TMS and ROV to be mechanically connected to the hydraulic A-frame. Conversely, when pivotable fingers 306 are in an open position, the umbilical termination socket of the umbilical cable is released by the pivotable fingers 306 and the umbilical cable is free to pass through the centre of housing 302.

Cylinders 303 of apparatus 301 are hoseless hydraulic cylinders, meaning that there are no hoses entering either of the two cylinders 303. In the prior art latch assemblies, there are two hoses (or more) providing hydraulic pressure to the single hydraulic cylinder to cause opening of the pivotable fingers. In the prior art, the fact that the hoses enter the cylinder is disadvantageous because when the pivotable fingers pivot open and shut, the cylinder also moves, and therefore the hoses move up and down. This movement can subject the hydraulic hoses to damage and cause them to become tangled.

In contrast, the two cylinders 303 of apparatus 301 are hoseless and instead port 308 is used to receive a first hydraulic pressure hose and port 309 is used to receive a second hydraulic return hose (not herein shown). Therefore, advantageously, each of the two hoseless cylinders 303 of the present invention has fewer hydraulic joints, fewer hydraulic fittings and * * * * * * * * * consequently fewer failure points and less hydraulic failure.

In the upper surface of housing 302 is a plurality of mounting holes 310 for attaching said housing to the hydraulic A-frame. * * e * * * * *

Figure 4 As in Figure 3, Figure 4 shows a perspective view of the apparatus 301 embodied in the present invention but instead in an open position. In an open position, umbilical cable is free to pass through the apparatus and therefore the TMS and ROV are not mechanically connected to the A-frame.

Apparatus 301 comprises a CNC precision-machined stainless steel circular housing 302 which advantageously does not corrode and does not require painting. This therefore eliminates the disadvantage of uneven paint layers which can interfere with the function of the latch assembly.

Hoseless cylinder 303 is connected to link plate 304 which itself is connected to pivot shaft 305. Pivot shaft 305 has a direct connection to pivotable finger 306. Hydraulic activation of cylinder 303 causes movement of both link plate 304 and pivot shaft 305 which consequently causes opening of pivotable finger 306. Only one hoseless cylinder 303, one link plate 304 and one pivot shaft 305 in relation to pivotable finger 306 are illustrated in Figure 4. However, apparatus 301 comprises a second hoseless cylinder, a second link plate and a second pivot shaft in relation to a second pivotable finger positioned in a directly opposing arrangement relative to the first pivotable finger on the periphery of housing 302. In the illustrated embodiment, hoseless cylinder 303 is directly bolted to housing 302 with four bolts. However, in alternative embodiments, alternative means of fixing can be used, as would be understood by the skilled person in the art.

Umbilical cable, or wire rope, not herein shown, passes through central region 307 of housing 302. When pivotable fingers 306 are in a closed position, the umbilical termination socket of the umbilical cable is grasped by the pivotable fingers 306 and the umbilical cable is secured at a fixed position. Advantageously, the system is capable of holding the umbilical termination socket of the umbilical cable on only one latch finger in the event that the other latch finger should fail. This level of redundancy provides a superior level of safety over prior art systems. Without a hoseless system, there would need to be more hydraulic joints and hydraulic finings in order to enable independent operation of the two latch fingers. There would clearly be disadvantages in terms of increased risk of hydraulic failure with an increased number of hydraulic hoses.

Conversely, when pivotable fingers 306 are in an open position, the umbilical termination socket of the umbilical cable is released by the pivotable fingers 306 and the umbilical cable is free to pass through the centre 307 of housing 302.

Cylinder 303 is hoseless, and instead of entering cylinder 303, the hydraulic pressure hose and the hydraulic return hose (not herein shown) each enter ports 308 and 309. Therefore, the hydraulic pressure hose enters a first port 308 and the hydraulic return hose enters a second port 309. Advantageously, each of the two hoseless cylinders 303 of the present invention has fewer hydraulic joints and hydraulic fittings and consequently **** * fewer hydraulic failure points. **** Instead of hydraulic hoses, a series of cross-drillings and internal * * grooves (not herein shown) provide a method of providing a direct hydraulic * * feed from the incoming hydraulic pressure hose to each hoseless hydraulic cylinder. These cross-drillings and internal grooves circumvent the need for * * hoses. The cross-drillings specifically comprise vertical and horizontal * 25 channels which route hydraulic fluid in vertical and horizontal directions into the cylinders. In the illustrated embodiment, the hydraulic fluid is hydraulic oil. The internal grooves on an upper surface of the housing circulate both pressure and return hydraulic oil.

Each pivotable finger may also comprise a rotary sensor, wherein each said rotary sensor is configured to provide positional information for the pivotable shaft. This positional information is visual or graphical information.

With this sensor, it is possible to obtain an exact position of where the pivotable fingers are positioned. This is used to operate a graphical representation of the pivotable fingers on a computer touchscreen of the operator control station. This is in direct contrast to the prior art in which it is not possible to know where the fingers are positioned.

In the upper surface of housing 302 is a plurality of mounting holes 310 for attaching said housing to the hydraulic A-frame.

Figure 5 A cross sectional view of the apparatus 301 embodying the present invention in a closed position is illustrated in Figure 5. As shown in Figure 5, housing 302 comprises two pivotable fingers 306 (or pivotable latch fingers) positioned in a directly opposing arrangement on the periphery of housing 302. When in a closed position as depicted in Figure 5, pivotable fingers 306 are configured to grasp umbilical termination socket 501 of the umbilical cable, thus securing the umbilical cable in a fixed position. This enables the TMS and ROV to be docked onto the A-frame when they are raised out of the sea, representing a safety feature so that there is no need for the winch to maintain tension to hold the TMS and ROV.

Hydraulic activation of the two hoseless hydraulic cylinders embodied in the present invention leads indirectly to movement of pivot shafts 305, movement of which causes movement of pivotable fingers 306 from an open position to a closed position as shown in Figure 5.

Instead of physical hydraulic hoses providing hydraulic fluid to the cylinders, housing 302 has a series of cross-drillings (shown further in Figure 9) to provide a direct hydraulic feed from the incoming hydraulic pressure hose to each hydraulic cylinder. Cross-drillings move hydraulic fluid in vertical and horizontal directions within the housing. In addition to cross-drillings, there are internal grooves (shown further in Figures 8 and 9) on a top surface of housing 302 which are configured to circulate both pressure and ret rn oil. Internal groove 502 circulates pressure oil and internal groove *** * * *** * * * * * * * 503 circulates return oil. The apparatus also comprises a top plate 505 which creates closed grooves 502 and 503. Top plate 505 is fitted with 0-ring seals. As illustrated in Figure 5, there are 3 0-ring seals 504 which create the two separate sealed grooves, 502 and 503. Mounting holes 310 are used to attach the housing 302 to the hydraulic A-frame.

Figure 6 A cross sectional view of the apparatus 301 embodying the present invention in an open position is illustrated in Figure 6. In this open position, the umbilical cable is free to slide up and down in the central region of housing 302. Housing 302 comprises two pivotable fingers 306 (or pivotable latch fingers) positioned in a directly opposing arrangement on the periphery of housing 302. When in an open position as depicted in Figure 6, pivotable fingers 306 are configured to release the umbilical termination socket of the umbilical cable (not herein shown), thus allowing the umbilical cable to move freely.

Hydraulic activation of the two hoseless hydraulic cylinders embodied in the present invention leads indirectly to movement of pivot shafts 305, movement of which causes movement of pivotable latch fingers 306. Each of the two hoseless hydraulic cylinders is indirectly connected to one pivotable finger via a linking arm and a pivotable shaft having a direct connection to the pivotable finger (as illustrated in Figure 3).

Instead of physical hydraulic hoses providing hydraulic fluid to the cylinders, housing 302 has a series of cross-drillings (shown further in Figure 9) to provide a direct hydraulic feed from the incoming hydraulic pressure hose to each hydraulic cylinder. Cross-drillings move hydraulic fluid in vertical and horizontal directions within housing 302. In addition to cross-drillings, there are internal grooves on a top surface of housing 302 which are configured to circulate both pressure and return oil. Internal groove 502 circulates pressure oil and internal groove 503 circulates return oil. The * * * * . * * * * * * * . * * * apparatus 301 also comprises a top plate 505 which creates closed grooves 502 and 503. Top plate 505 may be fitted with a number of 0-ring seals, and as illustrated in Figure 6, is fitted with 3 0-ring seals 504 which create the two separate sealed closed grooves, 502 and 503. Mounting holes 310 are used to attach the housing to the hydraulic A-frame. * * 20 * * * * *

Figure 7 A perspective view of a hoseless hydraulic cylinder 303 embodied in the present invention is illustrated in Figure 7. The invention embodied in the present invention comprises two hoseless hydraulic cylinders 303, facing in opposite directions on the periphery of the housing of the claimed apparatus.

A link plate is directly connected to cylinder 303 at point 701. The link plate connects to pivotable shaft (not herein shown), movement of which causes movement of pivotable latch finger (not herein shown).

Cylinder 303 is bolted to the housing, and in the illustrated embodiment, is bolted to the housing with four bolts. Four corresponding bolt holes 702 are shown in Figure 7.

The rear face of the cylinder incorporates openings 703 and 704 which allow the pressure and return oil to transfer between the housing and the cylinder. Hydraulic sealings are used to prevent leakage of hydraulic fluid between the housing and the cylinder. Any hydraulic sealing that would be known to the skilled person in the art may be known, an example of which are 0-rings.

* Figure 8 * * * Figure 8 shows a side view of the apparatus embodied in the present * 25 invention. Housing 302 is CNC precision-machined stainless steel circular housing. Hoseless cylinder 303 is shown on the periphery of housing 302 with a direct connection to link plate 304 which itself has a direct connection to pivotable shaft 305. Cylinder 303 is bolted to housing 302 with four bolts 801. Pivotable shaft 305 represents the second shaft, itself having an indirect connection to the second hoseless cylinder via a link plate (not shown in Figure 8, but featured on the opposite side of housing to hoseless cylinder 303).

Ports 308 and 309 in housing 302 are used to receive a first hydraulic pressure hose and a second hydraulic return hose (not herein shown).

Therefore, advantageously, each of the two hoseless cylinders of the present invention has fewer hydraulic joints, fewer hydraulic fittings and consequently fewer failure points and less hydraulic failure. In the illustrated embodiment, port 308 receives a first hydraulic pressure hose and port 309 receives a second hydraulic return hose (not herein shown).

Hydraulic pressure fluid is circulated in circumferential groove 502 and then moved by a series of horizontal and vertical cross-drillings (as illustrated in Figure 9) from housing 302 to cylinder 303. Return hydraulic fluid is moved in an opposite direction in the cross-drillings from cylinder 303 and circulated in circumferential groove 503 towards port 309.

** * * **** * * * * * * * * * * Figure 9 Figure 9 shows an alternative cross-sectional representation showing the pattern of cross-drillings in housing 302. Incoming hydraulic pressure fluid enters housing 302 at port 308 and is routed via horizontal cross-drilling 901 into circumferential groove 502. Groove 502 circulates incoming hydraulic pressure fluid. Hydraulic pressure fluid is then routed via vertical and horizontal cross-drilling 902 into cylinder 303 at point 704. Return hydraulic fluid is routed via horizontal and vertical cross-drilling 903 into groove 503 and then leaves housing 302 at port 309. Hydraulic fluid enters and exits cylinders 303 at openings in cylinder as shown in Figure 7 as 704 and 705. Any hydraulic sealing that may be considered suitable by the skilled person may be used to prevent leakage between crossing-drillings and cylinders.

Figure 10 Figure 10A shows a top view of the embodied apparatus and Figure 10B shows a simplified cross-sectional view of cross-drillings from the grooves to the cylinders.

Figure 10A illustrates mounting holes 310 for attachment of the embodied apparatus to the hydraulic A-frame. Openings 1001 in groove 502 represent the points at which incoming hydraulic pressure fluid which has been routed around groove 502 is directed into the cross-drillings. Openings 1002 in groove 503 represent the points at which return hydraulic fluid enters groove 503 from the cross-drillings.

In Figure 10B, a simplified cross-sectional view of cross-drillings from the grooves to the cylinders 303 is shown. The cross-section is taken at a half way point through the cylinders equivalent to points 704 and 705 as shown in Figure 7. As can be seen, openings 1001 correspond to a cross-section through a vertical cross-drilling which opens into groove 502.

Openings 1002 correspond to a cross-section through a vertical cross-drilling which opens into groove 503. **** * **** * 20 * * * * * * * * * * * *

Claims

Claims What we claim is: **** **** * ***** **** *. **** * dl* * * * * so * * O. * * Is. * So * * * * * * 1. Apparatus configured for attachment to a standard hydraulic A-frame onboard a vessel comprising: a housing configured to allow passage of an umbilical cable or wire rope through a central region, said housing comprising two pivotable fingers positioned in a directly opposing arrangement on the periphery of said housing, wherein each said pivotable finger is independently hydraulically driven to a first open position by one of two spring-loaded hoseless hydraulic cylinders situated in a directly opposing arrangement on said periphery of said housing perpendicularly to each said pivotable finger and wherein each said pivotable finger is closed under spring-action to a second closed position, wherein each said pivotable finger in said second closed position is configured to latch onto an umbilical termination socket on said umbilical cable or wire rope passing through said housing, and further wherein said housing comprises a first port for receiving an incoming hydraulic pressure hose and a second port for receiving a return hydraulic pressure hose, and further wherein said housing comprises a series of grooves and cross-drillings to provide a direct hydraulic feed from said incoming hydraulic pressure hose to each said hydraulic cylinder.
2. Apparatus according to claim 1, wherein each said hoseless hydraulic cylinder is indirectly connected to one pivotable finger via a linking arm and a pivotable shaft having a direct connection to said pivotable finger.
3. Apparatus according to claim 1, further comprising a rotary sensor attached to each said pivotable shaft, wherein said rotary sensor is configured to provide positional information for said pivotable shaft.
4. Apparatus according to claim 3, wherein said positional information is visual information.
5. Apparatus according to claim 1, wherein said umbilical cable or wire rope is a load-bearing steel armoured cable or rope configured to lower a tether management system and/or a remotely operated vehicle from said vessel underneath the sea.
6. Apparatus according to claim 1, wherein said housing is a precision-machined stainless steel circular housing.
7. Apparatus according to claim 1, wherein said cross-drillings are configured to move hydraulic fluid in vertical and horizontal directions within said housing.

****
8. Apparatus according to claim 1, wherein an upper surface of e**** said housing comprises mounting holes for attaching said housing to said ***** 20 hydraulic A-frame. ****^ 0*

******* * * * * ****** *
9. Apparatus according to claim 2, wherein each said hoseless * * hydraulic cylinder, linking arm and pivotable shaft is oriented in an opposite direction on said periphery of said housing. * *
10. Apparatus according to claim 1, wherein each said hoseless hydraulic cylinder is directly bolted to said housing.
11. Apparatus according to claim 10, wherein each said hoseless hydraulic cylinder is directly bolted to said housing using four bolts.
12. Apparatus according to claim 1, wherein said grooves are configured to circulate pressure and return oil.
13. Apparatus according to claim 1, wherein said housing further comprises a top plate.
14. Apparatus according to claims 12 and 13, wherein said top plate is configured to create closed grooves.
15. Apparatus according to claim 13, wherein said top plate comprises a plurality of 0-ring seals.
16. Apparatus according to claim 15, wherein said top plate comprises three 0-ring seals.
17. Apparatus according to any of claims 14 to 16, wherein said 0-ring seals are configured to create two separate sealed grooves. ******e** ****., ***
18. Apparatus according to claim 1, wherein a rear face of said * ** *** *** * * * *** * * 20 cylinder comprises seals configured to enable pressure and return oil to * transfer between the housing and the cylinder without a leak occurring. * ******* * *
19. Apparatus according to claim 1, configured to hold a SWL of 13.6 tonnes. * *°. 25 * * 22. Apparatus substantially as described herein and with reference to the accompanying drawings 3 to 10.