A METHOD TO SUPPLY AIR AND PROPELLANT TO A VESSEL IN WATER AND A DEVICE FOR BALANCING THE VESSEL ACCORDING TO THE WATER DEPTH

Abstract: In connection with a method for supply of air and operating means to a vessel which is located at a great depth, there are provided one or more pump stations (1) at suitable distances between the surface and the vessel. The pump stations (1) can be equipped with means for balancing to the water depth and pumps and possibly other means for transporting air and operating means to the next station or vessel.

Description: A met h od to supply air and propellant to a vessel in water and a device f or ba l ancing the vessel according to the Water depth. The invention concerns a method for supplying air and operating means to a vessel located at a great depth and a device for balancing a vessel in water, e.g. a salvage dock, barge, submarine, pump stations, subsea devices etc. Diving at great depths entails major problems with regard to air supply. Due to the considerable difference in pressure between the surface and the depth concerned, it will be neces¬ sary to bring along large quantities of air. When manoeuvering a vessel in water it can be difficult to achieve a stable descent and ascent, due, amongst other factors, to possible bias, erratic air supply, etc. Thus it is desirable to provide a device for balancing and positioning of vessels in water which, e.g., are biased and to provide a method and a device for further transport of air down to the depth concerned. The object of the invention is therefore to provide a method for supply of air and operating means to a vessel, wherein the method enables the air supply to be replenished, thus avoiding the transport of large quantities of air on board the vessel. A further object, especially during the employment of such a method, is to provide a device for balancing, submerging and positioning of such a vessel in water. The object of the present invention is achieved by providing one or more pump stations at suitable distances betwen the surface and a vessel, in order to maintain a constant pressure, and to equip the pump stations with means for balancing to the water depth, thus making the device depth-independent. A special object of the device is obtained when a compressed air supply is provided which is connected to a service tank with an overpressure chamber. Further features are obtained by means of the sub-claims. The invention will now be described in more detail by means of an embodiment which is illustrated by means of the drawing. The drawing comprises the following: Fig. 1 is a cross section of a pump station according to the invention, fig. 2 is a cross section of a pressure supply according to the invention, fig. 3 illustrates pump stations provided between a surface vessel and a submerged vessel, fig. 4 is a schematic representation of the diving, balancing, depth-independent and air supply principle according to the invention. Fig. 1 of the drawing shows a pump station 1 with a ballast chamber 2. Through the pump station 1 there are passed means 3, e.g. connection elements for cables or air input 16. The pump station 1 comprises an electrical compressor 4, which is controlled by an adjustable pressure sensor 8 which maintains a desired exit pressure 12, e.g. at 500m, of approximately 55 bar, i.e. at overpressure. There are further provided propul¬ sion means 5, 9, e.g. electrical motors for, amongst other things, operation of the compressor 4 and cooling devices 13, 14. A pressure controller 6 is connected to the compressor 4 for pressure control and the adjustable pressure sensor 8 is further connected to the pressure controller 6. For manoeuver¬ ing, the pump station 1 iε equipped with hydraulically driven propellers 17, operated by a hydraulic pump 7 which is con¬ nected to an oil cooler 14. Inside the pump station 1 there is provided an overpressure chamber 11 with a two-way valve 10. The pump station 1 is further equipped with an air cooler 13 and control means in the form of a control centre 15 with transmitting and receiving devices 18. Fig. 2 illustrates a compressed air supply in the form of an air storage bottle 19 with a pressure-actuated bottom 20 consisting of an orifice 21 for pressure equalization with a grid 22 and a first end cap 23 which iε threaded on the air storage bottle 19. At the other end there is provided a second end cap 24 with an air inlet 25. Inside the air storage bottle 19 there is provided a moveable bottom 20, with packing rings 26, which can be moved between the first end cap 23 and an end stop 27. Fig. 3 illustrates an example of the use of pump stations 1 between a surface vessel and a vessel in water. These pump stations are provided spaced at a specified distance apart, e.g. 500 metreε. Fig. 4 illustrates the device for balancing a vessel in water consiεting of a compreεsed air supply 29, e.g. according to fig. 2, or air supply from the surface 39, posεibly via pump stations 1, connected to a service tank 30 with an overpressure chamber 31, where between the pressure chamber 31 and the service tank 30 there is provided a two-way valve 32. There is further provided a compressor 33 between the compressed air supply 29 or surface air 39 and the service tank 30. Buoyancy tank(s) 28 with overpresεure εensors 34 are connected to the device. These are designed to control the pressure difference between an internal pressure in the buoyancy tank(s) 28 and an ambient water pressure. The compresεor 33 is provided in such a manner that it maintains the pressure in the service tank 30. In the buoyancy tank 28 there is provided a bottom valve 35 which is opened during both ascent and deεcent and the pressure sensor 34 also controls a presεure relief valve 36 during aεcent. The preεεure εensor 34 readε and determines the pres¬ sure difference between the buoyancy tanks 28 and an ambient water presεure. The preεsure difference can be adjusted con¬ tinuously in order to achieve the desiired rate of descent or ascent. Furthermore pressure senεorε 34 are installed at the same height on all the buoyancy tanks to enable the vessel to be trimmed in the desired or a horizontal poεition. Water- sensitive equipment such as electrical motors, cameras, relays and contacts, etc. are inεtalled in the overpressure chamber 31 with an automatic control, by means of the two-way valve 32, of a predetermined overpressure regardless of depth. There are further provided air supply valves 37, which are connected to the air supply from the surface or the pump station, on both sideε of the service tank 30, and check valves 38 are provided between the air supply 29 and the service tank 30. During descent and ascent the compressor 33 will automatically upgrade the air supply 29 and keep the volume of air in the air supply 29 constant in relation to the ambient water pressure. The method for supply of air and operating means to a vessel which is located at a great depth iε implemented by providing one or more pump stationε at suitable distances between the surface and the vessel. The pump station(s) 1 with, e.g., an eliptical εhape, compriεeε an electrically operated compressor 4, which is controlled by the adjustable preεεure sensor 8 which keeps the exit pressure 12 at approximately 55 bar overpressure. The pump station 1 is equipped aε an overpreεsure chamber, and is controlled by the two-way valve 10 and main¬ tains a predetermined overpressure in relation to the ambient presεure. For manoeuvering, the pump station 1 is equipped with hydraulically operated propellers 17. These are operated by an electrically-driven hydraulic pump 7, which iε cooled by an oil cooler 13. The overpreεεure chamber 11 iε equipped with an air cooler 12. For positioning, the pump station 1 is equipped with a control centre 15 and signal tranεmitter and receiver 18. The compreεεed air εupply constitutes a reserve εupply in the event of faultε in the air supply from the surface or the pump station. The presεure supply is not limited to the air storage bottle embodiment. It will also be posεible to employ other forms of compressed air supply. Conversely, it will also be posεible to employ the air storage bottle embodiment in other connectionε, such as a gas supply. A device, e.g. in the form of a salvage dock, can control the nearest pump εtation, which in turn controlε the next, an εo on up to the surface. The poεitioning εyεtem will be capable of poεitioning both the salvage dock and pump εtationε in a vertical position over the salvage object. A salvage dock which can be used in connection with the invention is described in Norwegian patent application no. 92 1774. The device according to the invention can be equipped with automatically controlled ascent, if any faults should arise in the signals from the surface. It can also be remotely con¬ trolled from the surface or from a mini-submarine.

Claims: PATENT CLAIMS 1. A method for supplying air and operating means to a vesεel which iε located at a great depth, characterized in that there are provided one or more pump stations (1) at suitable distanceε between the surface and the vessel and that the pump stations (1) are equipped with means for balancing to water depth and pumpε and possibly other means for transporting air and operating means to the next station or vesεel. 2. A pump station (1) for use in connection with a method according to claim 1, characterized in that the pump station (1) compriεeε cooling deviceε (13, 14) for, e.g., air and oil, that the pump εtation (1) compriεes control means conεiεting of, amongεt other thingε, a control centre (15) , a signal transmitter and a receiver (18) , and that it compriεeε pumpε (7) and/or operating meanε for propellerε (17) . 3. A device for balancing of a veεsel in water, e.g. a salvage dock, barge, submarine, pump stations, etc. characterized in that the device comprises a compresεed air supply (29) or surface air εupply (39) , connected to a εervice tank (30) with an overpreεεure chamber (31) , that there iε provided a co preεεor (33) between the εupply (29) or the εurface air supply (39) and the service tank (30) , that there are connected to the device buoyancy tank(s) (28) with over¬ pressure sensorε (34) , and that the overpreεεure sensors (34) are designed to control the preεεure difference between an internal preεεure in the buoyancy tank(ε) (28) and an ambient water preεεure. 4. A device according to claim 3, characterized in that the compreεεed air εupply (29) iε a bottle element (19) , preferably with a preεεure-actuated bottom (20) . 5. A device according to claim 3, characterized in that the εervice tank (30) haε an overpressure of approximately 50 bar in relation to the ambient presεure. 6. A device according to claim 3, characterized in that there iε provided a compreεεor (33) in order to maintain the preεεure in the service tank (30) . 7. A device according to claim 3, characterized in that there is provided a bottom valve (35) which iε opened both during ascent and descent. 8. A device according to claim 3, characterized in that the overpreεεure chamber (31) haε a two- way valve (32) , which independently of the depth automatically maintainε a conεtant predetermined preεεure. 9. A device according to claim 3, characterized in that the buoyancy tankε (28) have preεεure sensors (34) provided at the same height, and which control preεεure relief valveε (36) during aεcent. 10. A device according to claim 3 or 9, characterized in that the pressure difference between the internal presεure in the buoyancy tankε (28) and the ambient preεεure in the water controlε both the aεcent and the deεcent. 11. The employment of a bottle element with preεεure actuated bottom according to claim 4 aε preεεure source in a gas εupply.

Inventors: STROM EINAR, STROEM, EINAR
Applicants: STROM EINAR, STROEM, EINAR
Application year: 1993
Main classification: B63C11
IPC codes: B63C11