COMPENSATOR CYLINDER

Abstract

This utility model relates to high-pressure air systems with pressure compensation in the off-board equipment of an autonomous ultra-deep-sea vehicle operating under changing ambient pressure. The compensator cylinder comprises a robust housing with a separating element installed within the housing's interior to form two cavities, with end caps containing flow passages for supplying the medium. The housing is spherical, with upper and lower hemispherical sections and a central annular thickened section, rigidly connected to each other. The separating element is designed as an elastic separating membrane, hermetically seated with its flange in an annular groove formed in the center of a cylindrical surface within the annular section, and secured with an elastic open safety ring. Through holes, sealed with bolts, are also formed circumferentially on the outer side of the annular section.The removable upper and lower covers are provided with central openings in which the thrust plate rods are installed, located on the inner side of the housing and spring-loaded relative to the covers by coil springs. On the outer side of the covers, removable flange covers are installed, in which openings are made for the supply of high-pressure air and the ambient medium, respectively. The upper cover is equipped with a pressure differential protection unit, which includes two plugs installed in bushings and consisting of two parts connected by safety bridges. One part of each plug is threaded and screwed into the bushing, the other part is installed in the bushing with a seal, capable of movement in the event of the safety bridge being destroyed by excess pressure. 6 ref. fil., 1 fig.

Description

[0001] The field of technology to which the utility model belongs.

[0002] The utility model relates to high-pressure air systems with pressure compensation in the outboard equipment of an autonomous ultra-deep-sea vehicle operating under changing ambient pressure.

[0003] Technique level.

[0004] HYDAC diaphragm accumulators (High pressure diaphragm accumulators. HYDAC Product Catalog. - https: / / www.hydac.com / shop / en / high-pressure-diaphragm-accumulators-1000188068) are known for their diaphragm accumulators, which consist of a liquid and gas chamber with a diaphragm acting as a gas-tight separating element. The liquid chamber is connected to the hydraulic circuit, so an increase in pressure causes the diaphragm accumulator to fill and the gas volume to decrease. When the pressure drops, the compressed gas expands and forces the accumulated liquid back into the circuit. A disc valve is installed in the diaphragm bottom. When completely empty, it closes the hydraulic outlet, thereby preventing damage to the diaphragm. HYDAC diaphragm accumulators are available in two designs: welded and threaded.

[0005] The disadvantage is the inability to replace the membrane in the welded version, making it non-repairable during operation. These accumulators are used in hydraulic systems and are not intended for use in compressed air systems.

[0006] A pressure compensator (RU, No. 2590886, published July 10, 2016) for a subsea electrical installation is known. It has a rigid outer shell, which can be made, for example, of metal. A separating element—an elastic chamber or elastic bag—is located within this rigid outer shell. This elastic bag can be made of an elastic material such as rubber. This compensator has two openings, one at each end of the rigid cylinder. The first opening is intended to form a fluid connection between the pressure compensator and a subsea installation, such as a transformer or frequency converter. The subsea installation may contain a rigid pipeline to which the pressure compensator is connected. Fastening and sealing equipment can be used to connect and secure the compensator to this installation. The second opening is intended for communication with the external environment—seawater.Seawater can enter and exit the elastic bag through this second opening. The connection between the bag and the rigid cylinder at the second opening is watertight. Therefore, water can only enter the bag itself, not the space between the bag and the cylinder. The device is not intended for storing compressed air at a working pressure of P. раб 20 MPa. Replacing the bag requires complete disassembly of the device or its replacement.

[0007] The disadvantage is the inability to store a reserve of compressed air, which excludes the use of a compensator in the high-pressure air system of an ultra-deep-sea vehicle.

[0008] A spacecraft fuel tank for storing and delivering liquid components is known (RU Patent No. 2522763, published February 27, 2014). It comprises a sealed housing made of two hemispheres with inlet and outlet fittings and external fastening elements. The housing has a metal diaphragm of variable thickness located within the housing and hermetically sealed to it around the perimeter. The thickness of the diaphragm is greatest at the equatorial portion and gradually decreases toward the polar portion.

[0009] A disadvantage is the presence of a metal diaphragm, which limits its potential deformation, compensates for the pressure differential, and provides a useful compressed air reserve. This precludes the tank's use in the high-pressure air system of an ultra-deepwater vehicle. Furthermore, replacing the diaphragm requires complete disassembly of the device. Furthermore, with daily temperature fluctuations, the metal diaphragm periodically flexes, and its weak point is the diaphragm attachment to the tank body, reducing the device's reliability.

[0010] A device for equalizing pressure in a sealed housing of an autonomous device operating with a change in ambient pressure is known (RU No. 2764323, published 01 / 17 / 2022), adopted as a prototype and containing a durable housing in the form of a high-pressure cylinder, including a cylindrical part with covers at its ends, a piston installed in the cavity of the durable housing with the possibility of its reciprocating movement when the ambient pressure changes relative to the pressure in the sealed housing of the autonomous device with the formation in the cavity of the durable housing, when the piston moves, of a working zone isolated from each other on opposite sides of the piston, increasing with an increase in the ambient pressure, and a compensation zone connected to the cavity of the sealed housing of the autonomous device and increasing with a decrease in the ambient pressure.A cylindrical shell is installed at a predetermined distance around the cylindrical portion of the pressure-sensitive housing, forming an annular cavity filled with damping fluid. At least the central portion of the sealed cylindrical shell is made of an elastic material capable of changing shape as ambient pressure changes relative to the pressure in the sealed housing of the self-contained device. The device is configured to admit damping fluid into the working area of ​​the pressure-sensitive housing cavity, displacing a piston under its action when ambient pressure exceeds the pressure in the sealed housing of the self-contained device, and to return the damping fluid to the annular cavity under the action of the piston movement when the pressure in the sealed housing of the self-contained device exceeds ambient pressure.

[0011] The presence of a piston, which can jam due to minor deformations of the housing or the ingress of environmental particles between the piston wall and the housing, reduces the reliability of the device. The presence of an elastic shell installed outside the device's housing reduces the device's reliability when used during the movement of an autonomous ultra-deep-sea vehicle at depths of up to 11,000 m, as the environment directly impacts the elastic shell.

[0012] Also, the excessive number of additional components, such as piston seals, compensating pistons to protect the seals, additional seals, and tubes, increases the time required for inspection and replacement. Replacing the piston, elastic diaphragm, or seals requires complex operations such as draining the damping fluid from the annular cavity of the elastic shell and then refilling the annular cavity.

[0013] Disclosure of the essence of the utility model.

[0014] The technical problem is to create a large-sized compensator cylinder with a simple design that will ensure reliable operation in the high-pressure air system of an autonomous ultra-deep-sea vehicle as a storage vessel for compressed air with P раб up to 20 MPa with the ability to relieve the system from the effects of ambient pressure when it increases to 112 MPa, as well as accessibility and ease of maintenance, which will allow the use of the compensator cylinder outside the main body of the autonomous ultra-deep-sea vehicle, in a space that is unattended during the period of continuous operation of the autonomous ultra-deep-sea vehicle.

[0015] The technical result of the utility model is to increase the service life of the expansion cylinder by increasing its reliability and maintainability.

[0016] The technical result is achieved in that in a compensator cylinder containing a durable housing with a separating element installed in the internal volume of the housing to form two cavities, with end caps with through channels for supplying a medium, the housing is made of a spherical shape with upper and lower hemispherical sections and a central annular thickened section, rigidly connected to each other, the separating element is made in the form of an elastic separating membrane, which is hermetically installed with its flange in an annular groove made in the center of a cylindrical surface inside the annular section, and secured with an elastic open safety ring, and on the outer side of the annular section, through technological holes are also made along the circumference, plugged with bolts, while the removable upper and lower covers are made with central holes in which the rods of the thrust plates are installed,located on the inside of the housing and spring-loaded relative to the covers by coil springs, and on the outside, removable flange covers are installed on the covers, in which openings are made for the supply of high-pressure air and the surrounding environment, respectively.

[0017] The upper and lower hemispherical sections and the middle section can be connected by welding.

[0018] The supporting and sealing surface of the thrust plates can be made spherical, and their rods are equipped with stoppers and locks.

[0019] A nipple for connecting the high-pressure air system of the AGSA can be installed in the cover-flange of the upper cover.

[0020] The removable flange cover of the bottom cover can be made with a passage channel for the external environment and a cleaning filter.

[0021] The fastenings of the upper and lower covers can be made in the form of removable half-clamps.

[0022] The expansion cylinder can be made of titanium alloy.

[0023] Brief description of the drawing.

[0024] The essence of the utility model is explained by a drawing.

[0025] Fig. 1 shows a general view of the compensator cylinder, a longitudinal section at operating pressure P раб , exceeding the ambient pressure.

[0026] Implementation of a utility model

[0027] The compensator cylinder contains a durable body 1, consisting of two hemispherical and one central annular thickened sections, rigidly connected to each other, for example, by welding (Fig. 1).

[0028] The spherical shape of the housing increases its strength compared to the cylindrical housing of the prototype. The presence of a thickened central section allows for the creation of a mounting unit for removable membrane installation, including an annular groove with access holes and securing bolts.

[0029] An elastic separating membrane 2 in the form of a hemisphere is located inside the housing 1 and hermetically connected to it, the flange of which is fixedly sealed in an annular groove made in the center of the central annular section of the housing 1. An open safety ring 3 is installed in the upper part of the annular groove. The membrane 2 divides the internal volume of the compensator cylinder into gas and hydraulic cavities and ensures the tightness of the gas cavity.

[0030] The presence of one elastic membrane inside the housing instead of a piston and an outer elastic shell increases the reliability of the expansion cylinder and simplifies installation and dismantling work when replacing it.

[0031] The elastic portion of membrane 2 is movable within housing 1 from one extreme lower position to the extreme upper position. To prevent membrane 2 from breaking near the flange when turning it inside out, an open safety ring 3 is installed in the upper portion of the groove.

[0032] At the outer side of the central annular section of body 1, there are openings 4, sealed with bolts, which protect the openings from contamination and the ingress of foreign objects. Openings 4 are designed to facilitate the guaranteed sealing of membrane 2 in the annular groove of cylinder body 1 and to facilitate its removal. Air is released through openings 4, preventing the installation of membrane 2, and they also serve to monitor the installation of membrane 2.

[0033] A sealed upper cover 5 for the gas cavity and a lower cover 6 for the hydraulic cavity, each with a central through-hole, are mounted at the ends of housing 1. Covers 5 and 6 are held in place by fasteners. The fasteners for the upper and lower covers 5 and 6 are removable half-clamps.

[0034] To protect the membrane 2 from rupture when it rests against covers 5 and 6 in extreme positions, thrust plates 10 and 11 are installed on the upper cover 5 and the lower cover 6 inside the housing 1, which close the central outlet openings of covers 5 and 6.

[0035] Each thrust plate is provided with a central rod, which is installed in the central hole of the cover, while the thrust plate is spring-loaded against its cover with coil springs.

[0036] When membrane 2 is not applied to the thrust plate, the springs push the plate away from the cover, opening the openings for the fluid to flow into the compensator cylinder. The thrust plate bearing and sealing surface is spherical, and their stems are equipped with stoppers to prevent the plates from falling out of the covers.

[0037] Removable flange covers 7 and 8 with through-flow channels are installed on sealed removable covers 5 and 6. The removable flange covers provide the passage of media into the cavities of the expansion cylinder body 1, connection to the expansion cylinder of the high-pressure air system pipeline, and installation of a cleaning filter.

[0038] The lower cover 6 contains a removable flange cover 8 and a passageway for the external medium. To prevent foreign particles from the external environment from entering the hydraulic cavity of the housing 1, a filter element 9 is installed in the removable flange cover 8. This filter element consists of two protective discs with a fine mesh.

[0039] The top cover 5 contains a removable flange cover 7 and a passageway for compressed air from the high-pressure air system. A fitting for connecting the high-pressure air system of the autonomous ultra-deep-sea vehicle is installed in the flange cover 7.

[0040] The fastenings of the compensator cylinder are made in the horizontal plane in the form of three paws on the lower hemispherical part of the body 1.

[0041] The expansion cylinder is made of titanium alloy, which reduces its weight and protects it from the effects of the marine environment, which also increases its durability.

[0042] The device operates as follows. A compensator cylinder is installed in the high-pressure air system of an autonomous ultra-deep-sea vehicle (AUDV) outside the main hull. The compensator cylinder is designed to store the required supply of high-pressure air at an operating pressure of P to purge the ballast tanks of the AUDV. раб up to 20 MPa and ensuring unloading of the high-pressure air system from the effects of external hydrostatic pressure with an increase in ambient pressure from P раб up to 112 MPa when operating at depths of up to 11,200 m.

[0043] Before the ASGA is immersed, when the ambient pressure Pnar is lower than the pressure in the gas cavity, the compensator cylinder functions as a cylinder with the required high-pressure air reserve. When filling with the working medium (air) through the nozzle of the cover flange 7 and the passage channels of the cover 5, the membrane is in its lowest position on the thrust plate 11 in the cover 6 of the hydraulic cavity. The working medium occupies the entire volume of the device. The compensator cylinder functions as a cylinder with a high-pressure air reserve until the ASGA is immersed, reaching an ambient pressure of 20 MPa.

[0044] When the ASGA is immersed and the ambient pressure P increases нар over 20 MPa, the lower thrust plate 11 is pressed out by the external environment and through the channels in the cover-flange 8, filter 9 and in the cover 6, the environment penetrates into the hydraulic cavity, the membrane 2 is deformed due to the compression of the working medium (air) in the gas cavity to the current value P нарDuring operation, the elastic portion of membrane 2 can move within housing 1 from its lowest position to a position corresponding to the maximum hydrostatic pressure of the external environment of up to 112 MPa, which corresponds to operation at depths of up to 11,200 m. This relieves the pipelines and other components of the high-pressure air system from the effects of ambient hydrostatic pressure. The expansion vessel functions as a pressure compensator.

[0045] If ​​it is necessary to replace the membrane during the operation of the ASGA, the operations of disassembling and assembling the compensator cylinder are carried out in a minimal volume sufficient to eliminate the malfunction.

[0046] Remove the fasteners, then the top cover 5 from the housing 1 and remove the open safety ring 3 through the upper neck of the housing 1. Supply compressed air at a pressure of 0.3 MPa through a hose from the high-pressure air system and a nipple into one of the process openings 4 of the housing 1, having first unscrewed one bolt, and carefully remove the membrane 2. It is permissible to dismantle the flange of the membrane 2 by slowly pushing it out through the process opening 4 with a blunt rod with a diameter of 3 mm.

[0047] Installation of membrane 2 is performed in the following sequence. Carefully inspect the membrane and ensure that its surface is free of cracks, cuts, foreign inclusions, and any network of small cracks visible only when bent. Apply a thin layer of lubricant to the surface of the flange seat. Place membrane 2 inside housing 1, inserting the membrane flange into the annular groove and installing it in the seat around the entire perimeter without folds or corrugations.

[0048] Screw in the removed bolts of the access holes 4. Replace the top cover 5 and secure it with fasteners. Then, fill the hydraulic cavity with 10-15 liters and supply air through the top cover at a pressure of up to 0.5 MPa, which causes the membrane flange 2 to snap into place. Remove the top cover 5 and check the position of the membrane 2 in the flange area. After ensuring that the membrane 2 is positioned correctly, install the safety ring 3, aligning its ends. Then replace the top cover 5 and secure it with fasteners.

[0049] The design of the compensator cylinder is intended for its installation and operation outside the main body of the ASGA, in a space that is not serviced during the period of continuous operation of the ASGA.

[0050] Thus, the use of the utility model allows for the provision of

[0051] storing the required supply of high-pressure air for blowing out the ballast tanks of the ASGA at an operating pressure of Pwork up to 20 MPa;

[0052] unloading pipelines and other elements of the high-pressure air system from the effects of external hydrostatic pressure of the environment when the ambient pressure increases from 20 MPa to 112 MPa when operating at depths of up to 11,200 m);

[0053] use of fittings and equipment of a significantly simplified and lightweight design (with smaller weight and size characteristics) in the high-pressure air system due to the presence of unloading from the action of external hydrostatic pressure.

[0054] The design of the expansion cylinder ensures its maintainability, as well as accessibility and ease of maintenance without dismantling the product from the ASGA, which increases the service life.

[0055] Thus, the utility model ensures increased service life by increasing the operational reliability and maintainability of the expansion cylinder.

Claims

1. A compensator cylinder comprising a robust housing with a separating element installed in the internal volume of the housing to form two cavities, with end caps with through channels for feeding a medium, characterized in that the housing is made of a spherical shape with upper and lower hemispherical sections and a central annular thickened section, rigidly connected to each other, the separating element is made in the form of an elastic separating membrane, which is hermetically installed with its flange in an annular groove made in the center of a cylindrical surface inside the annular section, and secured with an elastic open safety ring, and on the outer side of the annular section, through technological holes are also made along the circumference, plugged with bolts, while the removable upper and lower covers are made with central holes in which the rods of the thrust plates are installed,located on the inside of the housing and spring-loaded relative to the covers by coil springs, and on the outside, removable flange covers are installed on the covers, in which openings are made for the supply of high-pressure air and the surrounding environment, respectively.

2. A compensator cylinder according to paragraph 1, characterized in that the upper and lower hemispherical sections and the middle section are connected by a welded seam.

3. A compensator cylinder according to paragraph 1, characterized in that the supporting and sealing surface of the thrust plates is made spherical, and their rods are equipped with stoppers and locks.

4. A compensator cylinder according to paragraph 1, characterized in that a fitting for connecting a high-pressure air system is installed in the cover-flange of the upper cover.

5. A compensator cylinder according to paragraph 1, characterized in that the removable flange cover of the lower cover is made with a passage channel for the external environment and a cleaning filter.

6. A compensator cylinder according to paragraph 1, characterized in that the fastenings of the upper and lower covers are made in the form of removable half-clamps.

7. The expansion cylinder according to paragraph 1, characterized in that it is made of a titanium alloy.

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