WO1988006998A1

WO1988006998A1 - Device for control of valves in cargo pipes at e.g. ships

Info

Publication number: WO1988006998A1
Application number: PCT/SE1988/000098
Authority: WO
Inventors: Hans Milton
Original assignee: Milton Marine Automation Ab
Priority date: 1987-03-09
Filing date: 1988-03-03
Publication date: 1988-09-22
Also published as: DK169146B1; SE8700964D0; SE8700964L; DK623488A; SE462963B; KR890700511A; DK623488D0

Abstract

The invention relates to a device for remote control of cargo regulating valves (3) actuated by adjusting means in cargo pipes (1) of cargo spaces, especially cargo spaces of tankers where the valve adjusting means (4) and cargo regulating valves (3) are disposed all over the ship. According to the invention a number of valve control units (10) are arranged to serve each by themselves a number of valve adjusting means (4) by controlling by way of hydraulic oil lines (9) said valve adjusting means (4) and consequently the cargo regulating valves (3). The valve control unit (10) comprises a hydraulic oil power source (30) and hydraulic valves (21, 22) for controlling hydraulic oil flows in the hydraulic oil lines (9). Said valve control unit (10) also comprises a pneumatic valve plate (13) in order to actuate the hydraulic valves by means of compressed air. The pneumatic valve plate is supplied with compressed air from an external compressed air source. Furthermore, said valve control unit (10) comprises an electronic block (11) in order to actuate pneumatic valves in the pneumatic valve plate (13) by means of electric current.

Description

Device for Control of Valves in Cargo Pipes at e.g. Ships

This invention relates to a device at remote control of cargo regulating valves actuated by adjusting means in cargo pipes of cargo spaces, especially cargo spaces in the form of cargo or ballast tanks of ships or other floating constructions, said valve adjusting means and cargo regulating valves being disposed over a certain area.

When loading and unloading tankers, i.e. ships transporting oil and other fluids, supply and discharge of the load of the ship are carried out by the tanks of the ship being filled and emptied, respectively, according to certain patterns. Cargo regulating valves actuated by adjusting means are arranged in the cargo pipes of the ship, i.e. pipes for supply and discharge of the ship load, which cargo regulating valves enable regulation of the liquid flow in said cargo pipes. As the cargo regulating valves are spread all over the ship and, moreover, the valves normally are in an explosion dangerous environment individual hydraulic control lines for each valve adjusting means are arranged according to today's technology. Accordingly a great many expensive hydraulic lines must be installed on the ship. Hydraulic oil is then supplied from a centrally located hydraulic oil unit thus providing all the valve adjusting means with hydraulic oil.

Thus, through the presence of centrally operable hydraulic adjusting means for cargo regulating valves in lines for supply and discharge of ship cargo and/or ballast the cargo and ballast of the ship can by simply distributed in such a way that the best possible sea properties of the ship can be obtained in dependence on i.a. weather and wind conditions. Also when separate ballast tanks occur the hydraulic valve adjusting means described above are used in order that the water content of the ballast tanks might be varied in a simple way. It is the object of this invention to provide an economically attractive alternative to the known technology described above, a number αf valve adjusting units spread along the ship being arranged according to the invention which are formed to be in explosion dangerous environment and comprise a hydraulic oil power source. Only expensive hydraulic oil lines need be drawn between the valve control unit and a number of hydraulic valve adjusting means for the cargo regulating valves located close to said unit, each valve control means according to the invention only serving a limited number of the hydraulic valve adjusting means occurring in the cargo pipes.

The object of the invention is realized in that the device has been given the features defined in the claims.

In addition to the very great economical advantages of a device according to the invention the inventive device is relatively insensitive to functional trouble through decentralization of the hydraulic functions as not the whole hydraulic system is destroyed when for instance a local leakage problem occurs.

Illustrative examples of the invention will be described in greater detail in the following with reference to the enclosed drawings, wherein Fig. 1 is a schematic and transparent perspective view of a ship equipped with a device according to known technology, Fig. 2 is a schematic and transparent perspective view of a ship equipped with a device according to the invention, Fig. 3 shows schematically how the inventive valve control unit is built, and Fig. 4 shows a section from Fig. 3 on a larger scale to clarify the structure of the valves.

In Figs. 1 and 2 a number of cargo pipes 1 are shown extending along the ship and intended to be passed by the liquid ship cargo and/or ballast. The cargo pipes 1 end in a number of cargo tanks (not shown) and the opening of the cargo pipes against the cargo tanks is designated by 2. Close to the openings 2 cargo regulating valves 3 for regulating the liquid flow to and from the cargo tanks are arranged. These valves 3 are either continuously adjustable or only provided with an open-closed-function. The valves 3 are actuated by valve adjusting means 4, the positions of the valves 3 thus being adjusted between an open and a closed position by the aid of the valve adjusting means from a control centre. It should be added that more than one cargo pipe 1 can end in the same cargo tank.

According to known technique, see Fig. 1, individual hydraulic control lines are used for each valve adjusting means 4, resulting in that a considerable number of control lines 5 for the valve adjusting means must be installed in the ship. A group of such lines is designated by 6 in Fig. 1. All these lines 5 are supplied with oil from a hydraulic oil unit (not shown) placed in the engine room or deckhouse of the ship.

According to the invention, as is apparent from Fig. 2, a number of valve control units 10 are placed in the ship, each valve control unit 10 being connected with a number of adjacent valve adjusting means 4 via hydraulic lines 9 for actuating the position of the cargo regulating valves 3. Thus, hydraulic oil lines only occur between the decentralized valve control units 10 and the adjusting means 4, thanks to which only a small number of hydraulic oil lines are required in the inventive construction. Fig. 3 shows schematically a valve control unit 10, which is enclosed in a casing and made in a design protected against explosion. The valve control unit 10 comprises an electronic block 11 electrically connected to the control room of the ship through a number of electric lines 12. Said lines 12 are doubled with respect to the supply of current to the electronic block and the transmission of control signals from and to said electronic block. The lines 12 also transmit signals from sensing means for indication of current positions of for example the valve adjusting means and the cargo regulating valves.

Moreover, the valve control unit 10 comprises a pneumatic valve plate 13 provided with a number of valves 14-16, the positions of which are controlled by means of the electronic block 11. The valves 14-16 in the pneumatic valve plate 13 are supplied with compressed air via a compressed air line 17 starting from a compressed air unit in the engine room of the ship. The compressed air lines are not shown in Fig. 2.

The valve control unit 10 further comprises a hydraulic valve plate 20 provided with a number of valves 21 arranged in pairs and the positions of which are controlled by means of compressed-air actuation via the pneumatic valve plate 13. The hydraulic valve plate 20 also comprises two valves 22 which are also compressed-air actuated via the pneumatic valve plate 13.

The valve control unit 10 also comprises a hydraulic pump 30 driven by a compressed-air operated motor 31 which is supplied with compressed air via the pneumatic valve plate 13. The valve control unit 10 also exhibits a hydraulic oil tank 33 connected via a hydraulic oil line system with the pump 30 and the valves in the hydraulic valve plate 20 from which the hydraulic oil lines 9 run to the valve adjusting means 4, as shown in Fig. 2.

Thus, the cargo regulating valves 3 can be operated via the valve adjusting means 4 centrally from the control room of the ship in that the electronic block of a certain valve control unit 10 is actuated remotely from there so that the valves in the pneumatic valve plate 13 enter the desired positions and let through in this way compressed air. Accordingly the valves in the hydraulic valve plate 20 will also enter the desired positions and hydraulic oil via the lines 9 can selectively be made to actuate the adjusting means 4 and consequently the valves 3 so that the position of the valves 3 can be controlled as desired as well as the supply of for example cargo oil or ballast water in desired quantities to the desired tanks of the ship. The operation of the hydraulic pump 30 is also remote controlled via the electronic block 11 and the pneumatic valve plate 13.

The electronic transmission to the electronic block is of a serial nature meaning that the number of electric lines is minimized. For safety reasons certain functions of the electronic block are doubled, damage for example to electric cables not causing acute operational trouble. The cargo quantity in the cargo tanks is preferable established through measurement of the level by means of level indicators. The position of the valve adjusting means is preferably recorded by the aid of electric sensing means connected to the electronic block 11 of the valve control unit 10.

It is also possible to provide the supply of pressure medium to the valve plate 13 by another gaseous or liquid medium than compressed air.

It will be appreciated that the inventive device also can be used for other spaces where valve adjusting means and valves are spread over a great area and where an explosion dangerous environment is present at the same time. Besides ships for example oil platforms, mines and the like can be mentioned. The invention is not restricted to what has been shown and described but amendments and modifications thereof are possible within the scope of the following claims.

Claims

Claims 1. Device for remote control of cargo regulating valves (3) actuated by adjusting means in cargo pipes (1) of cargo spaces, especially cargo spaces in the form of cargo or ballast tanks of ships or other floating constructions, said valve adjusting means (4) and cargo regulating valves (3) being disposed all over a certain area, c h a r a c t e r i z e d in that at least two valve control units (10) are arranged to serve each by themselves a number of valve adjusting means (4) by controlling the valve adjusting means (4) and consequently the cargo regulating valves (3) by way of hydraulic oil lines (9).

2. The device of claim 1, c h a r a c t e r i z e d in that the valve control unit (10) comprises a hydraulic oil power source (30) and hydraulic valves (21, 22) for controlling a hydraulic oil flow in the hydraulic oil lines (9) to the valve adjusting means (4).

3. The device of claim 2, c h a r a c t e r i z e d in that the valve control unit (10) comprises a pneumatic valve plate (13) for actuating the hydraulic valves (21, 22) by means of compressed air and that the pneumatic valve plate (13) is supplied by compressed air from an external compressed air source.

4. The device of claim 3, c h a r a c t e r i z e d in that the valve control unit (10) comprises an electronic block (11) in order to actuate pneumatic valves (14-16) in the pneumatic valve plate (13) by means of electric current.

5. The device of any one of claims 1-4, c h a ra c t e r i z e d in that the valve control unit (10) is embodied in a design protected against explosion.