GB2282657A - Fluid movement control system - Google Patents

Abstract

A fluid movement control system for use in controlling movement of fluid from one area to another, there being some division between the two areas, comprises at least one valve 20 through which fluid may flow, control means (not shown) for controllably supplying pressurized actuating fluid to the valve, and a single supply conduit 36 communicating with the control means and valve, the valve having a valve body defining an inlet and an outlet, at least one closure member 26 movable with respect to a seat 30, the closure member defining a linear actuator which is operative on the closure member, whereby pressurised actuating fluid passing through the conduit 36 will cause the linear actuator to move the closure member 26 from a first to a second position. In the various embodiments, the linear actuator takes the form of a piston or a bellows. A pressure sensing passage 39 may extend through the valve housing. The system is used for controlling ballast in offshore installation of tubular jacket structures for gas and oil platforms. <IMAGE>

Description

FLUID MOVEMENT CONTROL SYSTEM The present invention provides a new and improved fluid movement control system including one or more valves. The valves forming part of this system utilise one or more actuators defined as part of a closure member of the valve and which enable each valve to be controlled using only one supply conduit.

The system provides a more economical system than known prior art fluid movement control systems.

The present invention relates to a fluid movement control system which may be used in a wide variety of applications where fluid may be required to be controllably moved from one area to another and possibly moved again, said areas being at least partly separated by a dividing member. However, for ease of reference in the following description, the invention will be described in relation to ballast control systems used in offshore installation of tubular jacket structures. Such structures comprise the bottom founded support for offshore oil and gas platforms. Tubular jacket structures are generally constructed of steel. However, the system can be used where a dividing member is constructed of concrete, other metals, plastics, fiberglass, wood or any other suitable material or mixture of materials.

During construction of offshore oil and gas platforms, tubular jacket structures are moved from a construction site to the intended offshore platform site. Initially the structures are buoyant. Having been moved to the site the structure is then controllably rotated from a near horizontal to a substantially vertical attitude such that the main steel jacket is substantially vertical. This controlled rotation is achieved by controllably flooding the jacket structure and/or tanks attached to the structure with sea water in such a manner as to cause or assist in causing the structure to rotate.

Each jacket structure is usually divided by bulkheads or the like such that a number of tanks are formed within the structure. The jacket structure may also have tanks temporarily or permanently affixed thereto, which may also be wholly or partially flooded when rotating the tubular structure. Rotation of the structure is effected by selectively and controllably flooding tanks during the operation. The compartmentation of the structure into tanks improves the control of the uprighting operation, and provides stability in the event of unplanned flooding. After the structure has been substantially located in position, most if not all, of the tanks below the sea surface are flooded.

A typical tubular jacket structure used for a deep water offshore oil or gas platform may include 20 or more tanks. At least one flooding/venting port is provided for each tank which can be remotely opened or closed, as desired, during the uprighting operation.

Generally two such ports are provided per tank.

In the past, the flow of sea water into the tanks through the ports has been controlled by the remote operation of devices such as ball, plug or gate fluid flow valves. These valves have been remotely opened or closed, as required, by means of purpose attached actuators, activated by the application of hydraulic or pneumatic pressure, routed to the actuator through paired control tubing or hose lines. Such remotely applied pressure causes operation of an actuator which in turn opens or closes a valve. Such valve actuators are commonly operated by a pressurized liquid, controllably applied from a central control means.

Typically such a control means incorporates nitrogen gas under pressure as a primary energy source.

Because of the potentially severe nature of the offshore environment and the high costs resulting from the loss of a structure, such systems are required to be exceptionally reliable. In the past, such reliability has been gained by use of well known, but complex and hence costly components. Additionally, costs have been increased by the complexity and difficulity associated with the work of installing, checking and testing the component parts of the system.

The fluid movement control system of present invention provides a number of advantages by comparison with past methods. Cost is reduced and efficiency increased by the use of fewer and more simple components and by considerably reducing the work required to install system components. These advantages arise partly because of the inherently simpler system provided by the present invention and partly because of the low weight of valves including the actuator used according to the present invention which enables manhandling rather than crane handling during installation. A further reduction in cost is apparent because the present invention considerably reduces the time and complexity required to test and commission the system. Further, the simplicity of the system means that reliability is improved.The system is more reliable because it utilises a valve with less moving parts and which does not require the actuator to be connected to the valve but forms part of the closure member of the valve.

According to the present invention, there is provided a fluid movement control system for use in controlling movement of fluid from one area to another there being some division between the two areas; the fluid movement control system comprising at least one valve through which fluid may flow, control means for controllably supplying pressurized actuating fluid to a valve, a supply conduit communicating with said control means and valve; said valve comprising a valve body defining an inlet and an outlet, at least one closure member movable from a first to a second position such that flow of fluid through said valve may be controlled, said closure member defining a linear actuator which is operative on said closure member; and said linear actuator communicating with one supply conduit only whereby pressurised actuating fluid passing through said conduit will cause said linear actuator to move the closure member from said first to said second position.

Control means for controllably supplying actuating fluid to said valve/s, may comprise any suitable means to control the amount and pressure, if any, of actuating fluid supplied to each separate valve at any given time. The control means may be manually or automatically operated, or a mixture of both manual and automatic operation and may include one or more computers.

Control means comprises pressure supply means, selector means to control the amount, if any, of pressure being supplied to any particular valve at any one time, one or more fluid sources, and one or more conduits linking the various parts and linking the control means and supply conduit/s.

Pressure supply means may be any suitable means by which pressure can be applied to actuating fluid in a supply conduit or by which pressure can be withdrawn from said actuating fluid, including means for creating a negative pressure gradient. Pressure supply means comprises one or more energy sources to controllably act on said actuating fluid. Suitable pressure supply means comprises one or more pumps, gas energy packages acting directly or indirectly on the actuating fluid, fluid/fluid interfaces wherein one fluid applies pressure to another fluid, actuators for example screw operated actuators or a combination of these. More than one pressure supply means may be provided, for example, in the event of redundancy of one system during operation.

Selector means comprises any suitable means including one or more switches, taps, control valves, flow selector valves or a combination of these.

Preferably control means includes one or more pressure regulators, flow meters, pressure gauges to inform the operator of the pressure and flow status of the actuating fluid being supplied to any valve at any particular time and/or pressure release valves. Said meters and valves may be any meters or any valve suitable for the purpose, including those generally available commercially. Control means preferably further comprises one or more safety valves and/or accumulators filters, one way valves, fluid reservoir including filter means, safety means, one way valves, connector points at various stages to allow access or a combination of these.

The system may include one or more connector points to which portable control means may be connected in the vicinity of the valve, for example so that a diver or remote operated vehicle may operate one or more valves, said connection may enable operation of the valves independent of the control means.

Supply conduit may be any suitable conduit including, but not limited to one or more tubes, hoses or the like. Said supply conduit should be capable of withstanding the positive or negative pressure gradient operating on the actuating fluid within the conduit. Supply conduit may comprise one or more sections connected together and the diameters of the sections may vary from one another. Preferably one or more sections of supply conduit are flexible.

It will be appreciated that in at least some applications the control means will be located on a movable platform located proximate the structure and movably connected thereto. The supply conduit should be sufficiently flexible such that it will not fracture or puncture as a result of movement during operation of the fluid movement control system or whether as a result of planar or rotational movement or the action of waves and/or wind.

Preferably supply conduit is made of a material which does not, at least until after completion of the ballast control operation using the fluid movement control system, adversely react with or break down in the presence of the actuating fluid contained therein or due to corrosion or rust arising from immersion in the fluid in which the structure is submerged.

Suitable materials comprise steel, stainless steel, brass, copper, reinforced rubber, reinforced plastics, reinforced fibre glass or any combination of these.

Supply conduit may be coated with one or more materials. Suitable coating materials include paint, teflon, and other suitable materials or combinations of materials.

Each valve comprises a valve body which defines at least one inlet and outlet which may be any suitable shape or size including, but not limited to, generally cyclindrical, square or rectangular tube form. Preferably, each valve body comprises one or more ports, some or all of which may define said inlet/s and/or outlet/s. Preferably, at least that part of the valve body defining a port is generally cylindrical or square or rectangular shape. Most preferably the valve body defines substantially cylindrical port/s.

In one preferred embodiment wherein the valve body communicates with three separate areas, the valve body is generally T-shaped. Preferably a port is defined within each arm of the T-shape. Preferably each arm of the T-shaped body defines a generally cylindrical shaped port.

Each valve may be attached to the dividing member which divides the areas. Said dividing member may be any suitable means. Examples of dividing members include walls, bulkheads, a structure leg etc.

Preferably the valve body is attached by means which allows safe, easy and quick installation of the valve within the structure. The means of attachment may also enable quick and easy removal of the valve body.

In one embodiment, one or more body retaining members are connected to or form part of the valve body. In one form said retaining members comprise maintaining plates, retaining plates, doubler plates, fixing members attached to or forming a part of or which are embedded in the dividing member or a combination of these. Said retaining members locate and maintain the valve in position within the dividing member.

Preferably said retaining members also serve to reinforce the structure where the valve extends through the dividing member. Preferably, retaining members are fixable to or within the dividing member in such a way that the valve may be quickly installed and preferably such that the valve may be readily removed. Said retaining members may be attached to the structure by any suitable means, including but not limited to by means of screws, bolts, glue, welding, rivets, or any combination of these.

Further, the valve body may be supported by support means comprising struts, reinforcing members or the like.

Preferably proximate one or more valve inlets are filter means which restrict entry of extraneous materials or debris into the valve. In one form filter means comprises one or more strainer plates.

Closure member may be any suitable shape such that when the closure member is in the closed position it cooperates with another part of the valve to substantially prohibit fluid flowing through an inlet proximate which the closure member is located. In one embodiment closure member is slidable within a port proximate the inlet.

In one embodiment, closure member cooperates with one or more seating elements to form such a seal when in the closed position. The closure member and/or seating element may include one or more sealing members which may comprise any suitable material, including but not limited to O-ring seals, rubber, silicone, plastic and/or metal inserts or washers, or any combination of these.

Closure member may include one or more locating members. Preferably when one or more locating members are provided said closure member is slidably located about one or more of said locating members.

Preferably, said locating member extends through one or more valve ports. Locating member/s may be fixed in place by any suitable means including but not limited to welding, bolting, riveting, glueing or a combination of these. Locating member/s may be connected at one end only or at two ends or at other points. Locating member/s may be connected to valve body, a part of the valve, one or more filters or fixing members. In one preferred embodiment, said locating member is connected to at least one strainer plate. Preferably said locating member extends between a strainer plate proximate an inlet in communication with a fluid in which the valve is submerged and a strainer plate or other member of the valve body proximate. Preferably locating member is removably fixed within the valve.In one preferred form a locating member extends through one or more holes within one or more strainer plates and/or fixing plates and is fixed to said plate/s at least at one end.

Any locating member may comprise several parts.

In one preferred form a locating member includes one or more sleeves. Locating member may provide means for retaining other ports in place within the valve.

Locating member may include one or more sealing members to help seal an abutment with a closure member. Sealing member may be any suitable material including but not limited to O-ring seals, rubber, silicone, plastic, metal inserts and/or gaskets.

Locating member may include one or more locating heads.

The closure member defines at least one linear actuator which may be any suitable actuation means which may move the closure member as required.

Preferably, linear actuator comprises at least one expansion chamber which will operate on the closure member to move it from the first to the second position. One or more parts of the closure member may form part of a structure defining an expansion chamber. The valve may include one or more pressure plates to form a part of the structure defining the expansion chamber. Preferably said pressure plate/s are fixed to the locating member. In one embodiment there is defined as a part of the closure member a cyclinder in which a piston is slidable which causes the closure member to move from said first to said second position. Part of the expansion chamber may be defined by part of the valve body and/or other members on ports of the valve body.

In yet a further embodiment the closure member may be linear actuators. Said linear actuators may cause the closure member to move in opposite directions. In yet a further embodiment bias means may be excluded and said second linear actuator included to move the closure member from said second to said first position. Said second linear actuator is also defined as a part of the closure member.

Communicating with said linear actuator is at least one supply passage through which pressurized actuator fluid may flow. In one form the supply passage/s are provided by passage/s provided within said locating member. Supply passage/s may be provided by one or more conduits contained within the valve. Preferably the valve includes supply conduit connector point which communicates with supply passage/s. In one form said connector point comprises a recess including a screw thread. In another form it comprises a male and/or female member. Supply conduit may be connected to connector point by any suitable means. In another embodiment supply conduit may be fixed directly to said supply passage.

Bias means may be provided by any suitable means, including but not limited to one or more resilient members. In one embodiment bias means may be provided by hydrostatic pressure. Preferably bias means comprises one or more springs. In one embodiment bias means may be provided by one or more coil or disc springs.

In one embodiment a locating member extends through said bias means and may provide means to assist in locating said bias means in place. In one embodiment said bias means extends between at least one filter member and said closure member in another embodiment a bias means retaining member may be provided. Closure member may be adapted to receive a portion of bias means so as to assist in locating bias means in place within the valve and maintaining it in position. In one embodiment bias means combined with hydrostatic pressure acts to move said closure member from said second to said first position. In another embodiment hydrostatic pressure alone may provide said bias means. In another embodiment bias means may be set at a predetermined resistance such that when the valve reaches a predetermined depth, hydrostatic pressure will cause the valve to open or close as the case may be.

In yet a further embodiment the valve includes pressure sensing means to detect the pressure within the tank at any given time. Preferably the valve includes a presure sensing passage.

The valve may further include a closure member location indicator which may be any suitable means to inform an operator of the position of the closure member within the valve at any given time.

In one form said indicator comprises a rod attached to the closure member which rod can be observed by a diver.

Preferably the valve also includes means such that the valve can be operated by a diver or remote operated vehicle in the vicinity of the valve. In one form, such means may comprise manual operation by mechanically moving the closure member. In another form a local pressure fluid supply point may be provided such that a portable control means may be attached by a diver or ROV and operated to control the valve.

The valve body, body retaining members, closure member, filter means, seating elements, locating member, including any locating head, pressure plates, supply passage tubes, and bias means may be made of any suitable materials. Preferably each is made of a material which does not substantially deteriorate or corrode, at least until after completion of the ballast control operation, using the ballast control system. Suitable materials comprise steel, stainless steel, brass, copper, reinforced rubber, reinforced plastic, reinforced fibre glass concrete or any combination of these. One or more of the parts may be coated with one or more materials. Suitable coating materials include paint, teflon, and other suitable materials or combinations of materials.

It will be appreciated that the valve could be operated by means other than fluid pressure, such other means comprising a cable.

In figure la there is shown a schematic representation of a prior art ballast control system and in figure lb there is shown a schematic representation of a form of control means used in a prior art ballast control system of the type shown in figure la.

Particular embodiments of the invention will now be described by way of example only and with reference to the accompanying drawings of which: Figure 2a shows a schematic representation of a ballast control system according to one embodiment of the invention fitted to one leg of a tubular jacket structure which structure is of a similar type to that shown in figure la.

Figure 2b shows schematic representation of one form of control means which may be used as a part of the ballast control system as shown in figure 2a; Figure 3, shows a schematic cross-section, in two parts, of one embodiment of a valve which is suitable for use in a fluid movement control system according to the present invention.

In figures 3a and 3b there are shown a schematic front view of strainer plate 23 and schematic rear view of fixing plate 24 respectively.

In figures 4 to 13 inclusive, there are respectively shown schematic cross-sections in two parts of different embodiments of valves which may used in a fluid movement control system according to the present invention.

In figure 14 there is shown a schematic cross-section of yet a further embodiment of a valve suitable for use in a fluid movement control system according to the present invention, which valve communicates with three different area and includes two closure members.

These figures will now be described in more detail.

A schematic representation of a prior art ballast control system is shown in Figure la. In this figure there is shown one leg of a tubular jacket structure 1 including bulkheads 2 which divide said structure into tanks 3. Each tank includes valves 4 and 5 connected to ports 4a and 5a respectively. The valves enable fluid to enter or leave the structure as required. The operation of said valves is controlled by a control apparatus (details of an example of which are shown in figure lb) which communicates with valves 4 and 5 via supply conduits 6 and 7. Actuators 8 and 9 are connected to valves 4 and 5 respectively and are activated by the application of hydraulic or pneumatic pressure. The application of pressure through supply conduit 6 causes the valve to open.The application of pressure through supply conduit 7 causes the valve to close.

In Figure lb there is shown a schematic representation of one form of control means used for a ballast control system of the type shown in Figure la. Control means 400 is connected to supply conduits 6 and 7 and valves 401 are provided to control access of fluid between the control means and supply conduits. Control means 400 includes a fluid conduit 402 which divides at various points into a number of conduits which is in communication with supply conduits 6 and 7 and a fluid return conduit 403. A fluid reservoir 404 communicates with one end of each of conduits 402 and 403. Fluid reservoir 404 includes a filter valve 405 and filter 406, a vent 407 and a level gauge 408. Conduits 402 and 403 include isolation valves 409 proximate fluid reservoir 404 and filters 410. A number of other valves are also provided. Conduit 403 further includes one way valve 411.Pumps 412 are provided in communication with conduit 402 to pump fluid in a direction away from the fluid reservoir. Conduit 402 includes an external pump connector point 413 proximate which is a one way valve. Conduit 402 and 403 further include a selector flow direction valve 414, gauges 415 and flow meters 416.

Energy may be controllably supplied to pumps 412 by energy supply means 417. Energy supply means 417 comprises conduits 418 communicating with pumps 412 and energy supply packages 419 in the form of pressurised gas cyclinders. Generally the gas in said cyclinders is nitrogen or air. Conduits 418 further include isolating valves 420, crossover valves 421, flow adjustment valves 422, gauges 423, strainers 424 and controllable pressure regulators 425. Emergency gas inlets 426 are provided in communication with conduit 418 and include quick release connectors 427.

Exhauster valves 428 are provided in communication with pumps 412. Energy supply means 417 may operate to control flow of fluid within conduit 402 by direct action on fluid communicating with fluid in conduit 402 as shown in energy application means 429. Energy application means 42 comprises conduit 430 communicating with conduit 418 and accumulators 431, in which are located fluid which by control of selector flow direction valve 432 may be placed in communication with fluid in conduit 402.

In Figure 2a there is shown a schematic representation of one leg 11 of a tubular jacket structure, including watertight bulkheads 12 compartmenting the jacket into tanks 13, including a schematic represenation of part of a ballast control system according to one embodiment of the present invention. Tubular jacket leg 11 includes valves 14 a,b,c and d and 15 a,b,c,and d, valves 14 having supply conduits 16 a,b,c and d connected respectively thereto and valves 15 having supply conduits 17 a,b,c and d connected thereto. There are further provided strainers 19 to filter extraneous materials out of the fluid entering the tanks 13.

In Figure 2b there is shown a schematic representation of control means of the same general type as shown in Figure lb but adapted for use in the present invention. As will be clear by a comparison of figures 2b and 1b the control means comprises substantially less parts and is substantially less complex than that used for the conventional system depicted in Figure 1. It will also be clear from a comparison of Figures la and 2a that substantially fewer supply conduits are used. There is shown control means 500 which is connected to supply conduits 16 and 17. Control means 400 includes a fluid conduit 501 which at various points divides into a number of conduits. Energy source 502 is connected to fluid conduit 501 and comprises pressurised gas cyclinders. Connected to fluid conduits 501 are gauges 503, controllable pressure regulators 504.

In Figure 3 there is shown a schematic cross section, in two parts, of one emodiment of a valve which is suitable for use in a fluid movement control system according to the present invention. In one part the valve is shown in the closed position such that liquid or gas cannot pass from one side to the other and in the other part the valve is shown in an open position such that liquid or gas may pass through the valve. Valve 20 is connected to a jacket leg wall 21 of a tubular jacket leg structure by means of doubler plates 22. Valve 20 includes valve strainer plate 23 and fixing plate 24. A schematic front view of strainer plate 23 is shown in figure 3a. In figure 3b there is shown a schematic rear view of fixing plate 24. Extending through the valve body and affixed to strainer plate 23 and fixing plate 24 and located centrally within said body, is locating member 25.Slidably mounted on locating member 25 is closure member 26 which includes base 27 and head 28.

Connected to locating member 25 is pressure plate 29.

Closure member 26 is slidable in relation to pressure plate 29.

Valve 20 includes seating member 30 which includes abutment face 31. Closure member 26 includes in the vicinity of head 28 closure abutment face 32, which is a substantially complimentary to abutment face 31, such that when abutment faces 31 and 32 come into contact a seal substantially forms between closure member 26 and seating member 30 such that liquid is substantially restricted from passing through valve 20. Closure abutment face 32 incorporates an O-ring seal 33 to assist in sealing the abutment. during seals 33 are also included in a section of the base 27 proximate locating member 25 and in a section of the pressure plate 29 proximate closure member 26.

Base 27, pressure plate 29 and parts of locating member 25 and closure member wall 34 define an expansion chamber 35. A supply passage 36 is provided in locating member 25 and communicates with expansion chamber 35. Supply passage 36 communicates with supply conduit connection point 37 which comprises a recess including a screw thread. In use, actuator fluid passing through a supply conduit which is connected to supply conduit connector point 37 and controlled by the control means, passes through supply passage 36 and into expansion chamber 35 thereby causing the volume of expansion chamber 35 to increase thereby causing closure member 26 to slide relative to locating member 25 such that closure abutment face 32 moves apart from abutment face 31 thereby allowing fluid to pass through valve 20 from or to a tank.

Located between strainer plate 23 and base 27 is bias means in the form of a resilient spring 38. Said spring 38 biasses closure member 26 toward the closed position.

Also shown in Figure 3 is a pressure sensing passage 39 which may be connected to a pressure sensing gauge so as to allow pressure within the tank to be measured from time to time.

In Figure 4 there is shown a schematic cross-section, in two parts, one part shown in the open and the other part shown in the closed position, of another embodiment of a valve which may be used in a ffluid movement control system according to the present invention. Valve 40 comprises valve body 41, strainer plate 42, base plate 43, locating member 44, closure member 45, seating member 46, bias spring 47, supply passage 48 and supply tube connection point 49. Valve body 41 incorporates orifices 50 in body wall 51. Closure member 45 comprises closure head 52 in abutment with sleeve 53 and piston 54. Closure head 52 and sleeve 53 are slidable on locating member 44. Piston 54 comprises actuator plate 55 and expansion chamber 56. Sleeve 53 is connected to actuator plate 55.Expansion chamber 56 is defined by base plate 43, actuator plate 54 and part of valve body wall 51 and locating member 44. Supply passage 48 communicates with expansion chamber 55 and supply conduit connection point 49 and is located within locating member 44.

In Figure 5 there is shown a schematic cross-section in two parts, one part shown in the open position and the other in the closed position, of yet another embodiment of a valve which may be used in a fluid movement control system according to the present invention. Valve body 60 is connected to jacket leg wall 61. Valve body 60 includes strainer plate 62, base plate 63, closure member 65, seating member 66 and rods 67. Rods 67 are connected to seating member 66 which is in turn connected to jacket leg wall 61.

Base plate 63 is connected to the other end of said rods 67. Locating member 64 is connected to base plate 63. Closure member 65 comprises locating member 64 which comprises head 69, and leg 69a, closure base 70, closure sleeve 71 and expansion chamber 72.

Closure base 70 is slidably located on locating member 64.

Closure sleeve 71 slidably abuts locating head 69 such that a seal is substantially formed therebetween. O-ring seal 73 is located within a recess in a part of locating head 69 adjacent closure sleeve 71 to assist in sealing the abutment of these parts. Closure base 70 and part of closure sleeve 71, and locating member 64 define an expansion chamber 72. Supply passage 74 extends through locating member 64 such that it is in communication with expansion chamber 72 and control line connector point 75. Bias means in the form of a coil spring 76 extends between base plate 63 and closure base 69. Closure sleeve 71 when in the closed position abuts against seating member 66. Closure sleeve 71 includes a recess in one end in which is located O-ring seal 77 to assist in sealing the abutting surfaces such that fluid will not pass when the valve is closed.O-ring seal 78 is provided in a recess in closure base 70 adjacent locating member 64.

In Figure 6 there is shown a schematic cross-section in two parts, one part shown in an open position and the other part shown in a closed position, of a valve which may be used in a fluid movement control system according to the present invention. Valve body 80 is connected to jacket leg wall 81 utilising doubler plates 80b and 80c. Valve body 80 includes strainer plate 82, base plate 83, body wall 86, closure member 84 and bias means in the form of a spring 85. Closure member 84 is slidably located within and abuts against body wall 86 such that a seal is substantially formed therebetween.

Closure member 84 includes closure base 87, closure wall 90 and expansion chamber 88. Closure base 87 and base plate 83 and part of body wall 86 define an expansion chamber 88. Base plate 83 includes supply passage 89 communicating with expansion chamber 88 to which a supply conduit may be connected. Body wall 86 and closure member wall 90 include orifices 91 and 92 respectively. Orifices 91 and 92 are located such that when the closure member is in the open position orifices 91 and 92 are substantially aligned such that fluid may pass therethrough and hence through said valve. O-ring seals 93 are provided in recesses in closure member wall 90 to assist in sealing the abutment between closure member wall 90 and body wall 86.

In Figure 7 there is shown a schematic cross-section in two parts, one part shown in the open position and the other in the closed position of yet another embodiment of a valve which may be used in a fluid movement control system according to the present invention. Valve body 100 is connected to tank wall 101 and comprises closure member 104, seating member 110, rods 114 and support plate 113, bias means in the form of a spring 107 and supply passage 109. Closure member 104 comprises locating member 102 comprising locating head 103 and locating leg 103a, closure base 105 and closure wall 106 and expansion chamber 108.

Attached to tank wall 101 is seating member 110. End 111 of closure wall 106 is recessed to compliment that section of seating member 110 against which end 111 abuts when the valve is in the closed position.

Closure wall end 111 includes a recess in which is located O-ring seal 112 to assist in providing a seal between closure member 104 and seating member 110 when the valve is closed. Locating member 102 is connected to support plate 113 which is connected to tank wall 101 by support arms 114.

Supply conduit connector point 115 communicates with supply passage 109 and is located in support plate 113. It will be appreciated that a supply passage and supply conduit connector point might be located in closure member 104, for example it may located in closure base 105. O-ring seal 116 is provided in a recess in locating head 103 adjacent closure wall 106 to assist in sealing the abutment between locating head 103 and closure wall 106.

Spring 107 is located substantially within closure wall 106 and abuts at one end against locating head 103 and at the other against legs 116.

In Figure 8 there is shown a schematic cross-section in two parts, one part shown in the open position and the other part shown in the closed position, of yet another embodiment of a valve suitable for use in a fluid movement control system according to the present invention. In Figure 8 there is shown valve body 120 connected to jacket leg wall 121. Valve body 120 comprises strainer plate 123 including orifices 124, body sleeve 126 and closure member 127. Closure member 127 comprises locating member 122, closure sleeve 125, closure head 128, closure base 129, expansion chamber 131 and closure wall 130 which is slidably located within and proximate sleeve 125. Said body sleeve 126 and closure sleeve 125 being arranged such that a channel is formed between them in communication with orifices 124. Closure sleeve 125 is welded to strainer plate 123. Closure base 129 and part of strainer plate 123, locating member 122 and closure sleeve 125 define an expansion chamber 131. Extending between closure base 129 and locating head 132 of locating member 122 is bias means in the form of spring 133. Closure member 127 includes O-ring seals 134 to assist in sealing abutting parts of said closure member. Supply passage 135 is located within locating member 122 and is in communication with expansion chamber 131 and supply conduit connector point 136.

In Figure 9 there is shown a schematic cross-section in two parts, one part shown in the open position and the other part shown in the closed position of yet another embodiment of a valve suitable for use in a fluid movement control system according to the present invention. Valve body 140 is welded to jacket leg wall 141 and includes closure member 142, seating member 143 and valve wall 146 with orifices 147 extending therethrough. Closure member 142 comprises pressure plate 144, bias means in the form of a spring 145, closure head 148, closure base 149 and closure core 155. Pressure plate 144, closure base 149 and part of valve wall 146 and closure core 155 define an expansion chamber 150 which is in communication with supply passage 151 and supply conduit connection point 152.A section of closure head 148 abuts against seating member 143 when the valve is closed, and this section includes a recess in which is located O-ring seal 153 to assist in creating a seal between closure member 142 and seating member 143 when the valve is closed. Closure base 149 and pressure plate 144 also includes recesses in which are located O-ring seals 154 proximate their abutment against valve wall 146 and closure core 155 respectively.

In Figure 10 there is shown a schematic cross-section in two parts, one part shown in the open position and the other shown in the closed position of yet a further embodiment of valve for use in a fluid movement control system according to the present invention. In this Figure there is shown valve body 160 welded to tank wall 161. Valve body 160 includes valve body wall 162 which is connected by connecting members 163 to closure member 164. Closure member 164 comprises support member 165 and closure plate 166 and flexible membrane 167. Flexible membrane 167 extends between support member 165 and closure plate 166 and together with support member 165 and closure plate 166 defines expansion chamber 168. As shown support member 165 includes supply passage 169 and supply conduit connector point 170.It will be appreciated that supply passage 169 and supply conduit connector point 170 could equally be incorporated into closure plate 166. Valve body wall end 171 includes abutment face 172 which is substantially complimentary to that portion of closure plate 166 which abuts against it when the valve is closed. Abutment face 172 includes a recess in which is located O-ring seal 173. As shown in this figure bias means is provided by hydrostatic pressure acting on pressure plate 166 to move it toward a closed position.

In Figure 11 there is shown in two parts, one part shown in the open position and the other part shown in the closed position of yet another embodiment of a valve suitable for use in a fluid movement control system according to the present invention.

Valve body 180 is connected to tank wall 181 by means of doubler plates 180a and b. Valve body 180 comprises a first body member 182 and a second body member 183, both of which comprise substantially circular tubes. Second body member 183 includes body base 184. A gap 185 is provided between the first and second body members. First body member 182 includes a seating flange 186 extending therefrom. Valve body 180 further comprises closure member 187 which is slidably located proximate second body member 183 such that body wall 188 of second body member 183 is proximate closure wall 189. Closure member 187 comprises closure base 190 which extends beyond closure wall 189. Extending between the extension of closure base 189 and seating flange 186 is bias spring 191 which biases closure member 187 toward a closed position.Closure member 187 also includes expansion chamber 192 which is defined by body base 184, closure base 190 and part of closure wall 189. Supply passage 193 is located in body base 184 and communicates with expansion chamber 192. The first and second body members 182 and 183 are connected toeach other by cruciform shape locating member 194 which is welded to both body members.

Body wall 188 proximate closure wall 189 includes a recess in which is located during seal 195. End 196 of closure wall 189 includes a recess in which is located O-ring seal 197 which assists in sealing an abutment between end 196 and flange 186 when the valve is closed.

In Figure 12 there is shown a schematic cross-section in two parts, one part shown in the open position, the other part shown in the closed position, of yet another embodiment of a valve suitable for use in a fluid movement control system according to another aspect of the present invention. Valve body 200 comprises support plate 215, rods 216, sealing member 211, bias means in the form of spring 207 and closure member 204. Closure member 204 comprises locating member 202 comprising locating head 203 and locating leg 203a, closure wall 205, closure base 206, and expansion chamber 208. Sealing member 211 is fixed to tank wall 201 and abuts closure wall 205 which is slidable in relation to sealing member 211.

Sealing member 211 includes a recess in which is located O-ring seal 212 to assist in sealing the abutment between sealing member 211 and closure wall 205. Closure wall 205 includes cut-outs 213 at the inlet end thereof such that when the valve is closed the cut-outs are located on the opposite side of seating member 211 to tank 214, but which when the valve is open move such that at least a portion of the cut-outs is located on the tank side of the sealing member such that fluid is able to pass through the valve. Locating member 202 is supported on support plate 215. Located in support plate 215 is supply conduit connector point 210 which communicates with supply passage 209 which in turn communicates with expansion chamber 208. Support plate 215 is connected to tank wall 201 by means of rods 216.Face 217 of closure base 206 includes a recess in which is located O-ring seal 218 to assist in sealing the abutment between closure base 206 and locating member 202.

Locating head 203 also includes a recess in which is located O-ring seal 219 which assists in sealing the abutment between locating head 203 and closure wall 205. Expansion chamber 208 is defined by locating head 203, closure base 206 and part of locating leg 203a and closure wall 205.

In Figure 13 there is shown a schematic cross-section in two parts, one part shown in the open position and the other part in the closed position, of yet another embodiment of a valve which may be used in a fluid movement control system according to the present invention. Valve body 220 is welded to tank wall 221 and comprises strainer plate 222, body wall 223, body base 224, closure member 227 and bias spring 230. Valve wall 223 comprises seating flange 225 which includes abutment face 226. Closure member 227 comprises slidable piston plate 228, valve connector arm 229 and plug 231. When the valve is closed plug 231 seats against abutment face 226 forming a substantial seal therebetween, such that fluid cannot pass through the valve. Valve wall 223 includes appertures 232. Closure member 227 further comprises expansion chamber 232 defined by piston plate 228, body base 224 and part of body wall 223. Body base 224 includes supply passage 233.

In Figure 14 there is shown a schematic cross section of yet a further embodiment of a valve suitable for use in a fluid movement control system according to the present invention. In this Figure there is shown tank wall 300 and bulkhead 301 dividing the structure into two tanks 302 and 303 respectively. Extending through and connected to tank wall 300 by means of doubler plates 304 is valve 305.

Valve 305 comprises generally T-shaped body 306 defining three ports 307, 308 and 309. Valve 305 further comprises strainer plate 310 and fixing plate 311 which act as filters, and closure members 312 and 313 which are substantially similar to each other, each closure member comprising closure head 314, closure base 315, expansion chamber 316 and abutment face 317. Connected to and extending from strainer plate 310 to fixing plate 311 is locating member 318.

Locating member 318 is fixed in place by nuts 319.

Locating member 318 includes sleeves 320 comprising four sections. Sleeve sections 320 locate in place pressure plates 321 and reaction disc 322. Sleeve 320 defines in section 320a thereof first supply passage 323 which communicates with expansion chamber 314 of closure member 312. First supply passage 323 communicates with supply conduit connector point 324 which is formed within strainer plate 310. Locating member 318 defines a second supply passage 325 communicating with expansion chamber 316 of closure member 313. Bias means in the form resilient springs 326 abut closure bases 315. Spring 326 of closure member 312 extends between strainer plate 310 and closure base 315. Spring 326 of closure member 313 extends between reaction disc 322 and closure base 315.Body 306 includes seating members 327 against which abutment face 317 of closure members 312 and 313 abutt to form a substantial seal. Abutment faces 317 include O-ring seals 328. Further O-ring seals 329 are provided in pressure plates 321 and closure bases 315. Valve 305 further includes pressure sensing passage 333. Expansion chambers 316 are defined by closure base 315, pressure plate 321 and part of locating member 318 and closure wall 334.

As can be seen from Figure 14 the flow of fluid to or from tanks 302 and 303 may be controlled at least in part by closure members 312 and 313. If closure member 312 is open but closure member 313 is closed then fluid may flow to or from tank 303 but will not flow to tank 302. If both closure members 312 and 313 are open then fluid may flow to or from both tanks 302 and 303. If closure member 312 is closed but closure member 313 is open then fluid may flow to or from tank 302 to or from tank 303 thus enabling adjustment of the fluid within the two tanks without fluid entering or leaving the tanks to or from the external environment.

It will be appreciated that further valves of the type shown in Figure 14 may be incorporated into tanks 302 and 303 so as to improve venting and/or access to the tank. One valve in each tank may automatically vent the tank as fluid passes into it.

In figure 15 there is shown a schematic cross-section, in two parts, of yet another embodiment of a valve which is suitable for use in a fluid movement control system according to the present invention. The valve depicted in figure 15 is substantially similar to that shown in figure 3, except that the closure member 5 to 6 includes two expansion chambers 535 and 545 respectively.

Expansion chamber 535 is defined by base 527, pressure plate 529 and part of locating member 525 and closure wall 534. In communication with expansion chamber 535 is supply passage 536 which is in communication with supply conduit connector point 537. Expansion chamber 545 is defined by closure head 528, pressure plate 529 and part of locating member 525 and closure wall 534.

In communication with expansion chamber 545 is supply passage 546 which is in communication with supply conduit connector point 547. As shown valve 500 includes bias means 538. It will be appreciated, however, that expansion chamber 545 may be used to move closure member 526 from an open to a closed position and spring 538 may therefore be removed.

Claims (14)

CLAIMS:

1. A fluid movement control system for use in controlling movement of fluid from one area to another there being some division between the two areas; the fluid movement control system comprising at least one valve through which fluid may flow, control means for controllably supplying pressurized actuating fluid to a valve, a supply conduit communicating with said control means and valve; said valve comprising a valve body defining an inlet and an outlet, at least one closure member movable from a first to a second position such that flow of fluid through said valve may be controlled, said closure member defining a linear actuator which is operative on said closure member; and said linear actuator communicating with one supply conduit only whereby pressurised actuating fluid passing through said conduit will cause said linear actuator to move the closure member from said first to said second position.

2. A fluid movement control system as claimed in claim 1, wherein the valve is closed such that fluid cannot substantially pass therethrough when the closure member is in said first position and the valve is open and fluid may pass therethrough when the closure member is in the second position.

3. A fluid movement control system as claimed in claim 1 or claim 2, wherein said linear actuator includes at least one expansion chamber wherein said expansion chamber is in communication with one supply conduit only.

4. A fluid movement control system as claimed in any preceeding claim wherein said closure member is slidably located within the valve.

5. A fluid movement control system as claimed in any previous claim, wherein the valve further comprises at least one seating element which preferably includes a sealing member; said seating element interacting with said closure member such that when the closure member is in a closed position a seal is substantially formed between said closure member and said seating element such that fluid cannot substantially pass through the valve.

6. A fluid movement control system as claimed in any previous claim wherein the valve includes bias means operative on said closure member to bias said closure member toward said first piston.

7. A fluid movement control system as claimed in any previous claim wherein the valve includes a locating member on which is slidably located and movable relative to said locating member one or more closure members.

8. A control system as claimed in any previous claim wherein the closure member includes a second linear actuator which may move the closure member from said second to first position.

9. A fluid movement control system as claimed in any previous claim, wherein said valve includes in addition to an inlet communication with a first area, at least two ports, one port being in communication with a second area and another of the ports being in communication with a third area and at least one of these ports having a closure member located therein to control flow of fluid therethrough.

10. A fluid movement control system as claimed in claim 9 wherein one closure member is located proximate the inlet and at least one other closure member is located proximate at least one of the ports and said closure members may be individually controlled such that by control of one closure member fluid may be allowed to flow between the second and third areas without fluid passing from or to the first area and wherein by actuation of both closure members to their respective second positions fluid may flow between all these areas.

11. A fluid movement control system as claimed in any previous claim for use in providing ballast control.

12. A fluid movement control system as claimed in claim 1 and substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings Figures 3 to 13.

Amendments to the claims have been filed as follows CLAIMS: 1. A fluid ballast control system for use in controlling movement of fluid into and/or out of at least one tank which forms part of or is attached to a body to be ballasted; the fluid ballast control system comprising at least one valve through which fluid may flow, control means for controllably supplying pressurized actuating fluid to a valve, a supply conduit communicating with said control means and valve; said valve comprising a valve body defining an inlet and an outlet, at least one closure member movable from a first to a second position such that flow of fluid through said valve may be controlled, said closure member defining a linear actuator which is operative on said closure member; and said linear actuator communicating with one supply conduit only whereby pressurised actuating fluid passing through said conduit will cause said linear actuator to move the closure member from said first to said second position.

2. A fluid ballast control system as claimed in claim 1, wherein the valve is closed such that fluid cannot substantially pass therethrough when the closure member is in said first position and the valve is open and fluid may pass therethrough when the closure member is in the second position.

3. A fluid ballast control system as claimed in claim 1 or claim 2, wherein said linear actuator includes at least one expansion chamber wherein said expansion chamber is in communication with one supply conduit only.

4. A fluid ballast control system as claimed in any preceeding claim wherein said closure member is slidably located within the valve.

5. A fluid ballast control system as claimed in any previous claim, wherein the valve further comprises at least one seating element which preferably includes a sealing member; said seating element interacting with said closure member such that when the closure member is in a closed position a seal is substantially formed between said closure member and said seating element such that fluid cannot substantially pass through the valve.

6. A fluid ballast control system as claimed in any previous claim wherein the valve includes bias means operative on said closure member to bias said closure member toward said first piston.

7. A fluid ballast control system as claimed in any previous claim wherein the valve includes a locating member on which is slidably located and movable relative to said locating member one or more closure members.

8. A fluid ballast control system as claimed in any previous claim wherein the closure member includes a second linear actuator which may move the closure member from said second to first position.

9. A fluid ballast control system as claimed in any previous claim, wherein said valve includes in addition to an inlet communication with a first area, at least two ports, one port being in communication with a second area and another of the ports being in communication with a third area and at least one of these ports having a closure member located therein to control flow of fluid therethrough.

10. A fluid ballast control system as claimed in claim 9 wherein one closure member is located proximate the inlet and at least one other closure member is located proximate at least one of the ports and said closure members may be individually controlled such that by control of one closure member fluid may be allowed to flow between the second and third areas without fluid passing from or to the first area and wherein by actuation of both closure members to their respective second positions fluid may flow between all these areas.

11. A fluid ballast control system as claimed in any previous claim used in controlling the ballast of tubular jacket structures.

12. Use of a fluid ballast control system as claimed in any previous claim in the installation of offshore oil and gas platforms.

13. Use of a fluid ballast control system as claimed in any one of claims 1 to 11 to controllably manoeuvre an initially buoyant structure.

14. A fluid ballast control system as claimed in claim 1 and substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings Figures 3 to 13.