Anti-interference high-precision safety valve

Abstract

The utility model relates to an anti-interference high-precision safety valve which comprises a valve body, a valve clack, a valve seat and a spring pressure setting device. The check isolation device is characterized in that the check isolation device is arranged between the valve cavity and the outlet cavity, the outlet cavity and the valve cavity are sealed and isolated, medium pressure in the outlet cavity is prevented from entering the valve cavity to make contact with the valve clack and the spring, and the situation that pressure fluctuation of the medium in the outlet cavity influences a set pressure value and the sealing matching performance between the valve clack and the valve seat is prevented; and corrosion of external corrosive media to the spring and the valve clack is avoided, and the valve has the advantages of high pressure setting precision, reliable sealing performance, long service life of products and the like.

Description

Technical Field

[0001] The utility model relates to a safety valve, in particular to a spring-type safety valve. The utility model is suitable for safety valves in working conditions such as ships, offshore operating platforms, and diving pressure vessels. Background Art

[0002] At present, the safety valves used in ships, offshore platforms, and submersible pressure vessels have discharge ports immersed in or in contact with seawater. Changes in waves and tides act on the valve disc and spring through the discharge port of the safety valve, directly affecting the set pressure value and sealing reliability. In addition, seawater corrodes the spring, causing changes in the set pressure, resulting in low set pressure accuracy, poor sealing performance, and short product life. Summary of the invention

[0003] The utility model aims at the shortcomings of the prior art and provides an anti-interference high-precision safety valve which can isolate the external medium from contacting the valve disc and the spring, prevent the pressure fluctuation of the external medium from interfering with and corroding the spring and the valve disc, and has high set pressure accuracy, reliable sealing performance and long service life.

[0004] The technical solution to realize the utility model is:

[0005] An anti-interference high-precision safety valve comprises a valve body, a valve disc, a valve seat and a spring pressure setting device. The valve body comprises an inlet cavity and an outlet cavity, a valve cavity is provided between the inlet cavity and the outlet cavity, the valve seat is arranged between the inlet cavity and the valve cavity, the lower end surface of the valve disc is provided with a sealing surface which cooperates with the sealing surface of the upper end of the valve seat, the spring pressure setting device is arranged in the valve cavity on the back side of the valve disc, the spring pressure setting device comprises an adjusting spring and an adjusting sleeve, the adjusting spring is installed between the back side of the valve disc and the inner annular convex shoulder of the adjusting sleeve, and the adjusting sleeve is adjustably installed on the inner wall of the valve cavity; the feature is that a non-return isolation device is provided between the valve cavity and the outlet cavity The non-return isolation device comprises a check valve disc, a check valve seat, a preload spring and an adjustment ring; the check valve seat is arranged in the upper ring surface of the radial inner shoulder between the valve cavity and the outlet cavity, the check valve disc is installed on the upper side of the check valve seat, and its lower end surface is provided with a sealing surface that cooperates with the check valve seat, the center of which is connected with the center of the back of the valve disc through the valve stem, and the lower end of the valve stem is connected with the back of the valve disc through an axial floating device; the adjustment ring is connected with the external thread in the middle of the valve stem through the internal thread of the center hole, the preload spring is installed between the upper end surface of the adjustment ring and the lower ring surface of the radial inner shoulder, and a plurality of through holes are arranged in the annular plane of the adjustment ring.

[0006] In the above technical scheme, the axial floating device is composed of a radial outer boss at the lower end of the valve stem, a limit ring and an installation cavity on the back of the valve disc. The limit ring is connected to the inner thread of the installation cavity through an external thread, and the outer cylindrical surface of the valve stem and the inner hole of the limit ring are movably matched. The radial outer boss at the lower end of the valve stem is positioned and installed in the installation cavity by the limit ring, and the axial length of the radial outer boss is smaller than the axial length of the installation cavity.

[0007] In the above technical solution, the radial inner boss is arranged at the upper end of the positioning ring, the positioning ring is installed on the inner step of the valve body through the outer boss and the fixing sleeve, the outer circular surface of the lower end of the positioning ring is provided with an external thread, and an annular cavity is provided between the external thread and the inner wall of the valve cavity, and the adjusting sleeve is located on the upper side of the inner annular boss and is provided with an internal thread which cooperates with the external thread at the lower end of the positioning ring to be connected with each other.

[0008] In the above technical solution, a plurality of axial adjustment teeth are evenly arranged on the outer cylindrical surface of the adjustment sleeve, an adjustment hole is arranged on the valve body outside the axial adjustment teeth, and a positioning screw is installed in the adjustment hole.

[0009] The beneficial effect of the utility model compared with the prior art is that a check isolation device is provided between the valve cavity and the outlet cavity, which seals and isolates the outlet cavity from the valve cavity, blocks the outlet cavity medium pressure from entering the valve cavity and contacting the valve disc and the spring, prevents the outlet cavity medium pressure fluctuation from affecting the set pressure value and the sealing matching performance between the valve disc and the valve seat, avoids the corrosion of the spring and the valve disc by external corrosive media, and has the advantages of high set pressure accuracy, reliable sealing performance, and long product service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural schematic diagram of the utility model.

[0011] In the figure: 1 valve body, 2 inlet cavity, 3 valve seat, 4 valve disc, 5 adjusting spring, 6 adjusting sleeve, 7 axial adjusting tooth, 8 positioning screw, 9 adjusting hole, 10 adjusting ring, 11 positioning ring, 12 preload spring, 13 check valve seat, 14 fixing sleeve, 15 check valve disc, 16 outlet cavity, 17 nut, 18 sealing ring, 19 sealing gasket, 20 upper valve cavity, 21 through hole, 22 valve stem, 23 lower valve cavity, 24 limiting ring, 25 radial outer shoulder, 26 installation cavity, 27 inner annular shoulder, 28 radial inner shoulder, 29 annular cavity. DETAILED DESCRIPTION

[0012] like Figure 1The anti-interference high-precision safety valve comprises a valve body 1, a valve disc 4, a valve seat 3 and a spring pressure setting device. The valve body 1 has an inlet cavity 2 and an outlet cavity 16. The inlet cavity 2 is communicated with the inner cavity of a pressure vessel or a pipeline to introduce medium pressure into the lower end surface of the valve disc 4. A valve cavity is provided between the inlet cavity 2 and the outlet cavity 16. The valve seat 3 is arranged between the inlet cavity 2 and the valve cavity. A sealing surface that cooperates with the upper end surface of the valve seat 3 is provided on the lower end surface of the valve disc 4. The spring pressure setting device is arranged in the valve cavity on the back of the valve disc 4. The spring pressure setting device is composed of an adjusting spring 5 and an adjusting sleeve 6. The adjusting spring 5 is installed between the back of the valve disc 4 and the inner annular boss 27 of the adjusting sleeve 6. The adjusting sleeve 6 can be adjusted and installed on the inner annular boss 27 of the adjusting sleeve 6. The inner wall of the valve cavity is adjusted by adjusting the axial position of the adjusting sleeve 6 to adjust the elastic force of the adjusting spring, and set the pressure of the adjusting spring on the valve disc 4, that is, set the set pressure; it is characterized in that: a non-return isolation device is provided between the valve cavity and the outlet cavity 16, and the non-return isolation device includes a non-return valve disc 15, a non-return valve seat 13, a preload spring 12 and an adjusting ring 10; the non-return valve seat 13 is arranged in the upper annular surface of the radial inner shoulder 28 between the valve cavity and the outlet cavity 16, and the non-return valve disc 15 is installed in the outlet cavity 16 on the upper side of the non-return valve seat 13, and its lower end surface is provided with a sealing surface that cooperates with the upper end surface of the non-return valve seat 13, and its center is fixedly connected to the upper end of the valve stem 22, and the lower end of the valve stem 22 is connected to the back of the valve disc 4 The valve stem 22 and the valve disc 4 are connected through an axial floating device so that the valve stem 22 and the valve disc 4 can move axially relative to each other. The check valve disc 15 is fixedly installed on the upper end of the valve stem 22 by a nut 17. A sealing ring 18 is arranged between the outer cylindrical surface of the valve stem 22 and the check valve disc 15. The adjusting ring 10 is connected with the outer thread in the middle of the valve stem 22 through the internal thread of the center hole to separate the valve cavity into an upper valve cavity 20 and a lower valve cavity 23. The outer cylindrical surface of the adjusting ring 10 and the valve cavity are movably matched to form an axial guide mechanism for the valve stem 22 to prevent the valve disc 4 and the check valve disc 15 from radially deviating. The preload spring 12 is installed between the upper end surface of the adjusting ring 10 and the lower annular surface of the radial inner shoulder 28. By adjusting the adjusting ring 10 on the valve stem 22 Axial position, adjust the compression amount of the preload spring 12, adjust the sealing pressure ratio between the check valve disc 15 and the check valve seat 13, prevent the outlet chamber 16 medium from penetrating into the valve cavity, and set a plurality of through holes 21 in the annular plane of the adjusting ring 10. When the pressure in the inlet chamber 2 exceeds the set pressure to open the valve disc 4, the valve stem 22 is pushed to move upward, driving the check valve disc 15 to open, and the medium can be discharged to the outlet chamber 16 through the through hole 21. When the inlet chamber pressure drops back to less than the set pressure, the adjusting spring 5 pushes the valve disc 4 to close, and the preload spring 12 pushes the adjusting ring 10 to drive the valve stem 22 to move downward, and the check valve disc 15 and the check valve seat 13 are sealed and closed, preventing the outlet chamber 16 medium from entering the valve cavity.

[0013] The axial floating device is composed of a radial outer shoulder 25 at the lower end of the valve stem 22, a stop ring 24 and a mounting cavity 26 at the back of the valve disc 4. The stop ring 24 is connected to the inner thread of the mounting cavity 26 through an external thread. The outer cylindrical surface of the valve stem 22 and the inner hole of the stop ring 24 are movably matched, so that the valve stem 22 can be radially positioned on the stop ring 24 and can move relatively in the axial direction. The radial outer shoulder 25 at the lower end of the valve stem 22 is positioned and installed in the mounting cavity 26 by the stop ring 24. The axial length of the radial outer shoulder 25 is less than the axial length of the mounting cavity 26, ensuring that the preload spring 12 has sufficient axial adjustment margin. The stop ring 24 adopts a split ring structure to meet the installation process requirements.

[0014] The radial inner boss 28 is arranged at the upper end of the positioning ring 11, and the positioning ring 11 is installed on the inner step of the valve body 1 through the outer boss and the fixing sleeve 14. The fixing sleeve 14 adopts an external thread to cooperate with the internal thread of the outlet cavity 16, and the positioning ring 11 is pressed and installed on the inner step of the valve body 1, and a sealing gasket 19 is arranged between the outer boss of the positioning ring 11 and the inner step of the valve body 1; the outer cylindrical surface of the lower end of the positioning ring 11 is provided with an external thread, and an annular cavity 29 is provided between the external thread and the inner wall of the valve cavity; the upper side part of the inner annular boss 27 of the adjusting sleeve 6 is provided with an internal thread to cooperate with the external thread at the lower end of the positioning ring 11 to connect, and the axial position of the adjusting sleeve 6 on the positioning ring 11 is adjusted to change the compression amount of the adjusting spring 5 and set the set pressure value.

[0015] A plurality of axial adjusting teeth 7 are evenly arranged on the outer cylindrical surface of the adjusting sleeve 6, and an adjusting hole 9 is arranged on the valve body 1 outside the axial adjusting teeth 7. The axial adjusting teeth 7 are pushed through the adjusting hole 9, and the adjusting sleeve 6 can be rotated left or right to adjust the set pressure value. A positioning screw 8 is installed in the adjusting hole 9. The positioning screw 8 is fixedly and sealedly installed in the adjusting hole 9, and its end is pressed against the axial adjusting teeth 7 to realize the positioning of the adjusting sleeve 6 and prevent the rotation of the adjusting sleeve 6 from affecting the set pressure value.

[0016] Directional terms such as "upper", "lower", "left" and "right" in the present invention are only used for convenience of description and should not be construed as limitations on the technical solution.

Claims

1. An anti-interference high-precision safety valve, comprising a valve body (1), a valve disc (4), a valve seat (3) and a spring pressure setting device, wherein the valve body (1) has an inlet cavity (2) and an outlet cavity (16), a valve cavity is provided between the inlet cavity (2) and the outlet cavity (16), the valve seat (3) is arranged between the inlet cavity (2) and the valve cavity, the lower end surface of the valve disc (4) is provided with a sealing surface which cooperates with the upper end surface of the valve seat (3), the spring pressure setting device is arranged in the valve cavity on the back side of the valve disc (4), the spring pressure setting device comprises an adjusting spring (5) and an adjusting sleeve (6), the adjusting spring (5) is installed between the back side of the valve disc (4) and the inner annular boss (27) of the adjusting sleeve (6), and the adjusting sleeve (6) is adjustably installed on the inner wall of the valve cavity; wherein the characteristics are as follows: A check valve isolating device is provided between the valve cavity and the outlet cavity (16), the check valve isolating device comprising a check valve disc (15), a check valve seat (13), a preload spring (12) and an adjusting ring (10); the check valve seat (13) is arranged in the upper annular surface of a radial inner shoulder (28) between the valve cavity and the outlet cavity (16); the check valve disc (15) is installed in the outlet cavity (16) on the upper side of the check valve seat (13); a sealing surface is provided on the lower end surface of the check valve disc (15) which cooperates with the upper end surface of the check valve seat (13); and a sealing surface is provided on the lower end surface of the check valve disc (15) which cooperates with the upper end surface of the check valve seat (13). The upper end of the rod (22) is fixedly connected, and the lower end of the valve stem (22) is connected to the back of the valve disc (4) through an axial floating device; the adjusting ring (10) is connected to the external thread in the middle of the valve stem (22) through the internal thread of the center hole, and the axial guide mechanism of the valve stem (22) is formed between the outer cylindrical surface of the adjusting ring (10) and the valve cavity; the preload spring (12) is installed between the upper end surface of the adjusting ring (10) and the lower annular surface of the radial inner shoulder (28), and a plurality of through holes (21) are arranged in the annular plane of the adjusting ring (10).

2. The anti-interference high-precision safety valve according to claim 1 is characterized in that: The axial floating device is composed of a radial outer shoulder (25) at the lower end of the valve stem (22), a limit ring (24) and a mounting cavity (26) on the back of the valve disc (4); the limit ring (24) is connected to the inner thread of the mounting cavity (26) via an outer thread; the outer cylindrical surface of the valve stem (22) and the inner hole of the limit ring (24) are movably matched; the radial outer shoulder (25) at the lower end of the valve stem (22) is installed in the mounting cavity (26) below the limit ring (24); and the axial length of the radial outer shoulder (25) is smaller than the axial length of the mounting cavity (26).

3. The anti-interference high-precision safety valve according to claim 1 or 2 is characterized in that: The radial inner boss (28) is arranged at the upper end of the positioning ring (11); the positioning ring (11) is mounted on the inner step of the valve body (1) via the outer boss and the fixing sleeve (14); an outer thread is arranged on the outer circumferential surface of the lower end of the positioning ring (11); an annular cavity (29) is provided between the outer thread and the inner wall of the valve cavity; an inner thread is arranged on the upper side of the inner annular boss (27) of the adjusting sleeve (6) and is matched with the outer thread at the lower end of the positioning ring (11) and connected to each other.

4. The anti-interference high-precision safety valve according to claim 3 is characterized in that: A plurality of axial adjustment teeth (7) are evenly arranged on the outer cylindrical surface of the adjustment sleeve (6), an adjustment hole (9) is arranged on the valve body (1) outside the axial adjustment teeth (7), and a positioning screw (8) is installed in the adjustment hole (9).

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