Title of Invention

"A HIGH PRESSURE-RETAINING DEEP-SEA WATER SAMPLER"

Abstract

This invention relates a high pressure-retaining deep-sea water sampler. High pressure-retaining deep-sea water sampler collects the water sample at the predetermined depth from deep sea and will retain it at in situ hydrostatic pressure. A pressure preset spring loaded valve mechanism has been incorporated in the sampler which gets actuated when an equivalent hydrostatic pressure acts upon it. This hydrostatic pressure unseats the valve and allows entry of sea water into the sampler automatically at the predetermined depth. Once the sampler is filled with water the inside and outside pressures become equal. At this stage the compressed spring exerts the pressure on the valve pushing it back to its seat thus sealing it again. As the sampler is being hauled up, the differential pressure inside and outside the sampler goes on widening resulting into more and more positive sealing of the valve. The sampler brought on deck is connected to the sample transfer device to transfer the sample to the subsamplers under the same pressure for further analysis and study.

Full Text

This invention relates to a high pressure-retaining deep-sea water sampler. High pressure-retaining deep-sea water sampler collects the water sample at the predetermined depth from deep sea and will retain it at in situ hydrostatic pressure. A pressure preset spring loaded valve mechanism has been incorporated in the sampler which gets actuated when an equivalent hydrostatic pressure acts upon it. This hydrostatic pressure unseats the valve and allows entry of sea water into the sampler automatically at the predetermined depth. Once the sampler is filled with water the inside and outside pressures become equal. At this stage the compressed spring exerts the pressure on the valve pushing it back to its seat thus sealing it again. As the sampler is being hauled up, the differential pressure inside and outside the sampler goes on widening resulting into more and more positive sealing of the valve. The sampler brought on deck is connected to the sample transfer device to transfer the sample to the subsamplers under the same pressure for further analysis and study. The water samplers widely in use are Niskin type and Nansen type. These water samplers are lowered in the sea mounted on hydrographic wire. When the sampler has reached the desired depth the messenger is sent down along wire" to actuate the sampler to close and retain the water sample. This sample when brought on board ship does not retain the deep sea in situ pressure condition. Reference is made to H.W.Jannasch, C.O.Wirsen and C.L.Winget, 1973 , A bacteriological pressure retaining deep sea sampler and culture vessel. Deep Sea Research, Vol 20, pp 661-664 wherein the instrument was constructed and used as a deep - sea sampler and the culture vessel at in situ pressure for prolonged periods. Before lowering in the sea water the instrument is precharged with air and the distilled water into its chambers for sufficient air cushioning and to prevent the pressure gradient. The inlet valve is operated by a mechanical arm or by pressure device or a messenger. This instrument remains engaged for prolonged periods of incubation necessitating use of another instrument for collection of sample at the different location. Reference is made to 'A Pressure-Retaining Deep Ocean Sampler and Transfer System for Measurement of Microbial Activity in the Deep Sea' . Paul S.Tabor, Jody W.Deming, Kouichi Ohwada, Harry Davis, Meyer Waxman and Rita R. Colwell, 1981, Microbial Ecology 7:51-65. The instrument is very sophisticated in nature. Reference is made to 'Development Of A System To Collect And Cultivate Deep-Sea Microbes' ; Masanori Kyo, Tetsuya Inada, Toshiho Kikuma and Sigeru Nagai; Japan Marine Science & Technology Center; Japan. In this system deep -sea sediment is collected, brought on board maintaining the sample at in situ pressure. The sample is then diluted by mixing with sterilized sea water, microbes are isolated and cultivated in culture vessel. In the present invention (he single sampler is available for series of sampling operations as sample is transferred to subsamplers after every sampling operation. The operation is simplified as the inlet valve is operated automatically at the desired depth and does not require additional use of a messenger or any manipulator arm. A single sampler can be used for different depths by simply changing the valve inserts of different face area in contact with the ambient water. The instrument is very simple to assemble and operate. The instrument does not involve any high costs of manufacture or installation. Being a low cost instrument, oceanographers can afford to have several of them assembled and readily available for deployment during cruises saving in very expensive ship time. The main object of the present invention is to provide a high pressure-retaining deep-sea water sampler, which obviates the drawbacks as detailed above. In the drawing(s) accompanying this specification figure 1. represents the general arrangement of the high pressure-retaining deep-sea water sampler. Accordingly, the present invention provides a high pressure-retaining deep-sea water sampler which comprises of a pressure chamber (3) placed in the recess of the bottom plate (1) with a O-ring (10) in between; the piston (2) is placed inside over bottom plate; the center plate (4) is placed over the pressure chamber with second O-ring (10) in between; the valve housing (5) kept over the center plate with third CD-ring (10) placed in between; the spring (7) placed on the center plate in the recess provided; a pressure plate (8) is placed over the spring with the teflon insert (9) push fit inside pressure plate; the top plate (6) is placed over the valve insert with fourth O-ring (10) in its groove and clamped to the bottom plate by six tie rods and locknuts(11); outlet valve V1 (12) fitted to the port on valve housing with high pressure fittings, the charging valve V2 (13) is fitted at the opening in bottom plate; the PVC protective shroud (14) clamped to the top and bottom plates by means of screws (16) with delrin spacers (15) in between; the PVC jacketed wire slings (17) shackled to the lugs on top plate and other end for fitting a shackle to the hydrographic wire. In another embodiment of the present invention, the fixing means used are selected from nuts,bolts, screws, and locknuts tasting tie rods. In another embodiment of the present invention fastening means used are tie rods. In an embodiment of the present invention, the diameter and thickness and height of pressure chamber vary depending upon the depth of operation and sample capacity. In yet another embodiment of the present invention, the free floating piston is placed inside the pressure chamber to facilitate the transfer of the sample. In yet another embodiment of the present invention, the diameter and thickness of valve housing vary depending upon the depth of operation. In further embodiment of the present invention, the size and the number of springs in the valve housing vary depending upon the depth of operation. In further embodiment of the present invention, the area of the top face of the teflon valve insert in contact with the ambient water varies for different depth of operation. In an embodjment of the present invention the water sampler, is constructed from SS-316 material. The pressure chamber, the valve housing, valve plate, bottom plate, top plate, center plate all made of SS-316 and rated for about 2000m water depth operation and effectively transferable water sample capacity of 100cc. The thickness, diametre and the height of pressure chamber will vary as the depth of operation and the sample capacity . In another embodiment of the present invention the piston made of SS-316 is free floating inside the pressure chamber. The Nitrile high pressure seals backed by teflon rings are mounted over the piston with seal lip opening outwards which facilitates in effective transfering of 100cc of sample. In yet another embodiment of the present invention the valve housing diametre and thickness varies in the same way as the pressure chamber depending upon the depth rating. In still another embodiment of the present invention spring is also made of SS- 316. The spring is rated for 1400m water depth with teflon valve insert of top face dia 3mm. For higher depth operation the multiples of such spring (2-5 No) will have to be used. Accordingly, the size of the sampler will also vary. In still another embodiment of the present invention the valve insert made of teflon, the top face area of the insert is determined by the depth of operation. The tapered seat of the insert is completely in contact with the mating seat in the top plate and not in partial contact. In still another embodiment of the present invention all the tiebolts, nuts, washer and clamps are SS-316. High pressure valves and fittings and tubings are also SS- 316. The protective shroud is made of PVC pipe fitted with delrin spacers. The detailed working of the device is as follows : The invention is discussed and illustrated in detail as given below but the said disclosure as illustrated should not be construed to limit the scope of the invention. The high pressure water sampler (figure 1) consists of bottom plate, piston, pressure chamber, center plate, valve housing, top plate, spring, valve plate, valve insert, 0- rings, outlet valve V1 with tube and fittings and the protective shroud. All the components are assembled as shown in figure 1. Connect a charging valve V2 (13) to the bottom plate(1). Prime this valve and tube with distilled water and close V2. Close outlet valve V1(12). A laboratory trial is carried out to determine the pressure at which the spring loaded inlet valve insert (9) unseats. This will indicate the depth of operation at which the sample will be obtained. Two PVC jacketed wire slings (17) are clamped to the lugs on top plate(6) by D-shackles. The hydrographic wire is shackled to the slings and the sampler is ready for lowering. A deep sea pinger is also attached to the hydrographic wire at a distance of 2m above the sampler. The sampler is lowered into the water and the depth is monitored from pinger data as well as from meterwheel indicator. When the desired depth is reached the winch is stopped. Here the ambient hydrostatic pressure acts on the teflon valve insert (9) through the port P (figure 1). This pressure unseats the teflon valve and water makes entry into the sampler. The samplei is left for about 10 minutes to stabilize and collect the sample. When the sampler is completely filled with the water the pressures inside and outside the sampler become equal and at this stage the spring pressure will push the valve back against the seat in top plate (6) guided by the pressure plate (8). Then the sampler is hauled up. As the sampler rises, the differential pressure within the sampler and outside goes on increasing. This results in more and more positive sealing of the sample as the sampler is brought on board. The pinger and sampler are disconnected from the wire. The protective shroud (14) is removed and sampler is laid horizontally taking care that the valves and tubes do not get damaged. The sampler can then be connected to the sample transfer system wherein the distilled water is charged from charging valve(13) pushing the piston (2) upwards facilitating the transfer of sample to the subsamplers through outlet valve (12) without change in the pressure. Maximum care must be exercised while opening and closing the valves. The sampler is then opened, cleaned and reassembled for next operation. The protective shroud serves as a protection for valves and tubes from harsh underwater currents and also during handling on board. The size of the sampler varies depending upon the depth of operation and also the sample quantity. The present water sampler construction is rated for about 2000m with SS-316 cylindrical pressure chamber ID-8cm, OD-12cm and thickness of top and bottom plates - 2cm. The water sampler has a sample capacity of 100cc and is incorporated with the spring (7) operating at 1400m water depth. The teflon valve insert has face area of 0.07cm2 (dia 3mm). The sampler can be used with the same spring for lower depths by simply changing over the teflon valve inserts of bigger area exposed to ambient water, e.g. when face area of the insert is 0.126cm2 (dia 4mm), then the sample collection takes place at about 770m. Higher depth operation can be accomplished by use of multiple springs and valve inserts of different areas. The main advantages of the sampler are : 1. It samples at the desired depth automatically without use of messenger or manipulator arm. 2. It retains the water sample at the in situ pressure. 3. It facilitates to transfer the sample to subsampler without change in the pressure. 4. Single sampler can be used for various depths by simply changing over the valve inserts of different face area exposed to the ambient water. 5. Same sampler can be made ready for next operation after a couple of hours. 6. The sampler is very simple to assemble and operate. 7. Manufacturing and installation costs are very low. One can afford to have number of such samplers assembled and readily available for deployment at any time thus saving in valuable ship time. We claim : 1. A high pressure-retaining deep-sea water sampler which comprises in combination a chamber capable of holding and retaining water sample at in-situ hydrostatic pressure, the said chamber being provided with an inlet charging valve having pressure preset spring loaded valve mechanism capable of actuating when an equivalent hydrostatic pressure acts upon it, wherein the said charging valve V2 (13) connected to an opening in bottom plate (1), a pressure chamber (3) being placed in the recess of the said bottom plate (1) with a O-ring (10) in between; a piston (2) is placed inside the pressure chamber, and a center plate (4) being placed over the said pressure chamber with a second O-ring (10) in between; and a valve housing (5) being provided over the center plate with third O-ring (10) being placed in between; a spring (7) being placed on the said center plate in the recess provided; a pressure plate (8) being placed over the said spring with the teflon insert (9) being pushed to fit inside the pressure plate wherein the top plate (6) being placed over the valve insert with fourth O-ring (10) in its groove and clamped to the said bottom plate by fastening and fixing means and the outlet valve V1 (12) being fitted to the port on said valve housing with high pressure fittings, the charging valve V2 (13) is fitted at the opening in bottom plate; the PVC protective shroud (14) being clamped to the top and bottom plates by means of screws (16) with delrin spacers (15) in between; the PVC jacketed wire slings (17) being shackled to the lugs on top plate and other end of the said slings being fitted by a shackle to the hydrographic wire. 2. A High pressure-retaining deep-sea water sampler as claimed in claim 1 wherein the fixing means used are selected from nuts, bolts, screws, and locknuts tasting the tie rods. 3. A High pressure-retaining deep-sea water sampler as claimed in claim 1to 2 wherein fastening means used are tie rods. 4. A High pressure-retaining deep-sea water sampler as claimed in claim 1 to 3 wherein, the pressure chamber diameter, thickness and height vary depending upon the depth of operation and sample capacity. 5. A High pressure-retaining deep-sea water sampler as claimed in claim 1 to 4 wherein, the free floating is inside the pressure chamber to facilitate the transfer of the sample. 6. A High pressure-retaining deep-sea water sampler as claimed in claim 1- 5 wherein, the diameter, thickness of valve housing vary depending upon the depth of operation. 7. A High pressure-retaining deep-sea water sampler as claimed in claim 1 - 6 wherein, the size and the number of springs in the valve housing vary depending upon the depth of operation. 8. A High pressure-retaining deep-sea water sampler as claimed in claim 1- 7 wherein, the area of the top face of the teflon valve insert in contact with the ambient water varies for different depth of operation. 9. A High pressure-retaining deep-sea water sampler substantially as herein described with reference to the examples and drawings accompanying this specification.

Documents:

373-del-2000-abstract.pdf

373-del-2000-claims.pdf

373-del-2000-complete specification (granted).pdf

373-del-2000-correspondence-others.pdf

373-del-2000-correspondence-po.pdf

373-del-2000-description (complete).pdf

373-del-2000-drawings.pdf

373-del-2000-form-1.pdf

373-del-2000-form-19.pdf

373-del-2000-form-2.pdf