CN219035686U

CN219035686U - Pressure vacuum relief valve

Info

Publication number: CN219035686U
Application number: CN202222859153.4U
Authority: CN
Inventors: 请求不公布姓名
Original assignee: Finekay Tianjin Valve Manufacturing Co ltd
Current assignee: Finekay Tianjin Valve Manufacturing Co ltd
Priority date: 2022-10-28
Filing date: 2022-10-28
Publication date: 2023-05-16
Anticipated expiration: 2032-10-28

Abstract

The utility model discloses a pressure vacuum relief valve, which comprises a vacuum relief valve shell, wherein the top of the vacuum relief valve shell is fixedly connected with a pressure relief valve shell, valve seats are fixedly connected with the inner bottoms of the vacuum relief valve shell and the pressure relief valve shell, valve seat gaskets are jointly pressed between the two valve seats and adjacent vacuum relief valve shell and pressure relief valve shell respectively, and valve disc assemblies are respectively and tightly attached to the tops of the two valve seats. The inventive valve discs 2 inches (50 mm), 3 inches (75 mm) and 4 inches (100 mm) take the form of the valve disc assembly seal of example one. Valve disc 6 inches (150 mm), 8 inches (200 mm), 10 inches (250 mm) and 12 inches (300 mm) take the form of the valve disc assembly seal of example two. Different sealing designs are provided according to different sizes, and the design covers the full series of valves in the API2000 standard.

Description

Pressure vacuum relief valve

Technical Field

The utility model relates to the technical field of pressure vacuum relief valves, in particular to a pressure vacuum relief valve.

Background

The pressure vacuum relief valve is a protective device for the top of a storage bin in the chemical industry.

The existing pressure vacuum relief valve has the following problems when in use:

valve structure problem:

1. the valve cavity structure design of the current pressure/vacuum relief valve (breather valve) has a plurality of pressure breaking points, wherein the breaking points comprise the inner wall of the cavity, the roughness of the valve body and the direction change of steam.

2. In a valve cavity of a pressure/vacuum relief valve (a breather valve) in pipeline connection or in a closed environment, vortex is generated in the opening process of a valve disc assembly when the valve works, the vortex can cause turbulent flow and mixed flow which influence the lifting of the valve disc to form, and the turbulent flow and the mixed flow can directly or indirectly influence the opening state of the valve when the valve works, so that the turbulent flow and the mixed flow are also a great important factor for causing valve flutter and frequency jump.

3. The problem of excessive pressure collapse of the valve disc assembly is particularly pronounced at very low set pressures of 0.5kpa to 2.5kpa for the relief valve. When the pressure loss of the inlet is more than 3%, the valve disc assembly in motion is opened to generate a flutter phenomenon.

4. The occurrence of valve flutter is very easy to cause material fatigue of metal and soft sealing materials, so that the mechanical performance of a pressure/vacuum relief valve (breather valve) is reduced, and serious equipment hidden trouble is caused.

5. The bleeder performance is low and the bleeder capacity cannot meet a predetermined bleeder amount.

6. The sealing performance of the valve is poor before pressure relief.

7. The pressure difference of the back seat is large, and the pressure point of resealing the valve after pressure relief is low.

8. The valve and the valve seat thereof can not be replaced quickly after being damaged.

Valve disc assembly problem:

1. the structural seal pattern of the valve disc is unitary and the same structural seal pattern of the valve disc assembly is not suitable for providing an effective seal for all sizes of valve. A single valve disc construction may affect the opening of the valve resulting in the formation of secondary hazards to the reservoir.

Because of the structural requirement, the membrane pressing plate in the 2.6-12 inch valve disc assembly is made of 304 or 316 thin plates, and when the thin plates are pre-tightened by nuts, the pressing plate is deformed, so that the basic position fixing and pre-tightening effects cannot be formed on the membrane.

The valve disc in the 3.6-12 inch valve disc assembly is manufactured by stamping and spinning a stainless steel sheet. The stamped annular structure can bring certain rigidity compensation for the valve disc of the small-size valve, but the valve disc of the large-size valve is quite insufficient in rigidity especially at the vacuum end, and the valve disc is often bent upwards instantaneously after the vacuum instantaneous overpressure of the large-size storage tank occurs.

4. When the valve reaches the set pressure, in the valve disc lifting process, the bottom resistance of different ranges can be generated in the pretightening annular region of the valve rod at the bottom of the valve disc and the nut, and the bottom resistance is changed along with the change of the lifting height of the valve disc. The bottom resistance affects the overall lift and stability of the valve disc assembly. There is a need to reduce the bottom resistance of the bottom of the valve disc.

5. The bottom of the valve disc assembly is generally planar, and steam inevitably causes energy loss of a part of lifting in the process of pushing the valve disc assembly to lift.

Disclosure of Invention

The utility model aims to solve the defects in the prior art and provides a pressure vacuum relief valve.

In order to achieve the above purpose, the present utility model adopts the following technical scheme: the utility model provides a pressure vacuum relief valve, includes the vacuum relief valve casing, the top fixedly connected with pressure relief valve casing of vacuum relief valve casing, the equal fixedly connected with disk seat in the interior bottom of vacuum relief valve casing and pressure relief valve casing, two the disk seat has the disk seat gasket with the joint pressure between adjacent vacuum relief valve casing and the pressure relief valve casing respectively, two the top of disk seat is all laminated and is equipped with the valve disc assembly, two the air current deflector is all installed to the bottom of valve disc assembly, the top of vacuum relief valve casing and the top of pressure relief valve casing all are equipped with the valve gap casing, two the bottom of valve gap casing all the butt has the spoiler, the top the interior top of spoiler evenly butt has a plurality of first gag lever posts, and threaded connection between first gag lever post and the pressure relief valve casing, the bottom the interior top of spoiler evenly butt has a plurality of second gag lever posts, and threaded connection between second gag lever post and the vacuum relief valve casing, two the guide end of valve gap casing all sliding connection has the guide post, and the guide post is connected with adjacent valve disc assembly.

Further, two the valve disc assembly all includes first valve rod, and fixed connection between first valve rod and the guide post, the surface of first valve rod is from last to cover down in proper order to be equipped with first valve plate, first FEP diaphragm, first packing pad and first hexagonal nut, and threaded connection between first hexagonal nut and the first valve rod, and air deflector offsets with first FEP diaphragm, air deflector passes through first screw fixation in the bottom of first valve rod.

Further, two the valve disc assembly all includes the second valve rod, and fixed connection between second valve rod and the guide post, the surface of second valve rod is from last to cover in proper order to being equipped with second valve plate, spacer disc, backup pad, second FEP diaphragm, second compress tightly gasket and second hexagon nut down, and threaded connection between second hexagon nut and the second valve rod, and the air current deflector offsets with the second FEP diaphragm, the air current deflector passes through the bottom of second screw fixation at the second valve rod.

Further, washers are pressed at the bottoms of the two valve cover shells, a plurality of threaded bolts are connected between the two valve cover shells and the adjacent pressure relief valve shell and the vacuum relief valve shell respectively, the threaded bolts penetrate through the corresponding washers respectively, nuts are connected to the outer surfaces of the threaded bolts in a threaded mode, and the threaded bolts are connected with the adjacent pressure relief valve shell and the adjacent vacuum relief valve shell in a threaded mode.

Further, the two valve seats are respectively connected with an inner hexagon bolt together with the adjacent pressure relief valve housing and the vacuum relief valve housing.

Furthermore, a vacuum end cavity is formed at the valve of the vacuum relief valve shell, a pressure end cavity is formed at the valve of the pressure relief valve shell, and both the vacuum end cavity and the pressure end cavity adopt an R angle correction design.

Further, a wire mesh is commonly pressed between the vacuum relief valve housing and the adjacent valve seat gasket.

Further, the top ends of the two valve disc assemblies are fixedly connected with a first counterweight and a second counterweight.

Further, a plurality of connecting bolts are connected between the vacuum relief valve shell and the pressure relief valve shell together, and bolt gaskets are sleeved on the outer surfaces of the connecting bolts.

The pressure end is opened:

when the material is conveyed into the storage tank due to operation in the tank, the steam space in the material storage tank. The opening action of the pressure vacuum relief valve when the set pressure is reached is as follows: the pressure in the tank pushes the pressure vacuum relief valve open and is lifted along with the pressure end of the pressure relief valve, and the pressure end comprises a valve disc assembly. The valve disc assembly reseals with the valve seat when the pressure drops to 90% of the set pressure. The pressure end is provided with a plurality of first limiting rods which are used for preventing the valve disc assembly from being reset according to a preset track.

The pressure vacuum relief valve employs a 10% overpressure valve disc technology, and the unique 90 ° downward skirt design of the pressure end valve disc assembly facilitates the pressure end valve disc assembly opening height reaching 1/4 of the flow channel diameter, the maximum opening value, after 10% overpressure.

And (3) opening a vacuum end:

when the storage tank transfers materials outwards due to operation, the materials flow out to cause the inside of the storage tank to be in vacuum, and when the set vacuum value is reached, the opening action of the pressure vacuum relief valve is as follows: the vacuum end of the pressure vacuum relief valve is opened and then moves together, the valve disc assembly is lifted upwards, and the vacuum end of the valve is opened. When the vacuum pressure is raised to 90% of the set vacuum, the valve disc assembly reseals in cooperation with the valve seat.

The utility model has the beneficial effects that:

1. valve disc 2 inches (50 mm), 3 inches (75 mm) and 4 inches (100 mm) take the form of the valve disc assembly seal of example one. Valve disc 6 inches (150 mm), 8 inches (200 mm), 10 inches (250 mm) and 12 inches (300 mm) take the form of the valve disc assembly seal of example two. Different sealing designs are provided according to different sizes, and the design covers the full series of valves in the API2000 standard.

2. The valve disk assembly adds a polished air deflector and a 90 degree turned down edge of the valve disk, directs steam to change the direction of steam flow in a layout, and reduces pressure loss of the valve disk assembly to the steam

3. The inner wall of the valve cavity is designed in a 120-degree arc shape, so that the reflection angle of the steam fluid is increased, and the disturbance fluid acts on the valve cover and the spoiler.

4. The valve disc assembly turbulence guard, the valve disc assembly lifts a portion of the steam out of the way with the valve disc. Wherein a partial turbulence is created which collides with the valve inner wall and is reflected to the turbulence hood of the valve disc assembly, which is designed to reduce the fluctuating influence of turbulence on the reflected fluid in the longitudinally elevated space of the valve disc assembly.

5. The valve seat and the valve disc component can be quickly disassembled by the integral modularized design, and the shutdown repair time is shortened.

Fep separator as sealing material meets the sealing requirement at low set pressure.

7. The sealing performance of the valve seat is excellent before and after pressure relief.

8. The design layout of the airflow deflector is compatible with a full lift valve and a proportional lift valve, and the airflow deflector is used for lifting the total steam discharge amount after lifting and opening.

Drawings

FIG. 1 is an exploded view of a pressure vacuum relief valve;

FIG. 2 is a perspective view of a valve seat in a pressure vacuum relief valve;

FIG. 3 is a cross-sectional view of an air flow deflector in a pressure vacuum relief valve;

FIG. 4 is a perspective view of a spoiler in a pressure vacuum relief valve;

FIG. 5 is a cross-sectional view of a pressure vacuum relief valve;

FIG. 6 is a schematic diagram of a valve disc assembly according to the second embodiment.

Wherein, 1, the nut; 2. a threaded bolt; 3. a valve cover housing; 4. a gasket; 5. a spoiler cover; 6. a first valve stem; 7. a first stop lever; 8. a connecting bolt; 9. a bolt gasket; 10. a pressure relief valve housing; 11. a vacuum relief valve housing; 12. a guide post; 13. a first counterweight; 14. a second limit rod; 15. a second counterweight; 16. a first valve plate; 17. a first FEP separator; 18. an airflow deflector; 19. an inner hexagon bolt; 20. a first compression pad; 21. a first hex nut; 22. a valve seat; 23. a valve seat gasket; 24. a silk screen; 25. a vacuum end cavity; 26. a pressure end cavity; 27. a second valve stem; 28. a second valve plate; 29. a spacer disc; 30. a support plate; 31. a second FEP separator; 32. a second compression pad; 33. a second hex nut; 34. and a second screw.

Detailed Description

Embodiment one:

as shown in fig. 1-5, a pressure vacuum relief valve includes a vacuum relief valve housing 11 characterized by: the top fixedly connected with pressure release valve casing 10 of vacuum release valve casing 11, the equal fixedly connected with disk seat 22 in the interior bottom of vacuum release valve casing 11 and pressure release valve casing 10, the joint pressfitting has disk seat gasket 23 between two disk seats 22 and the adjacent vacuum release valve casing 11 and the pressure release valve casing 10 respectively, the top of two disk seats 22 is all laminated and is equipped with the valve disc assembly, air deflector 18 is all installed to the bottom of two valve disc assemblies, the top of vacuum release valve casing 11 and the top of pressure release valve casing 10 all are equipped with valve cover casing 3, the bottom of two valve cover casings 3 all butt has spoiler 5, the even butt in interior top of top spoiler 5 has a plurality of first gag lever posts 7, and threaded connection between first gag lever posts 7 and the pressure release valve casing 10, the even butt in interior top of bottom spoiler 5 has a plurality of second gag lever posts 14, and threaded connection between second gag lever post 14 and the vacuum release valve casing 11, the guide end of two valve cover casings 3 all sliding connection has guide post 12, and guide post 12 is connected with the adjacent valve disc assembly.

The two valve disc assemblies comprise a first valve rod 6, the first valve rod 6 is fixedly connected with the guide post 12, a first valve disc 16, a first FEP diaphragm 17, a first compression gasket 20 and a first hexagonal nut 21 are sequentially sleeved on the outer surface of the first valve rod 6 from top to bottom, the first hexagonal nut 21 is in threaded connection with the first valve rod 6, an air deflector 18 abuts against the first FEP diaphragm 17, and the air deflector 18 is fixed to the bottom of the first valve rod 6 through a first screw.

The bottoms of the two valve cover shells 3 are respectively pressed with gaskets 4, a plurality of threaded bolts 2 are respectively connected between the two valve cover shells 3 and the adjacent pressure relief valve shell 10 and the vacuum relief valve shell 11 together, the threaded bolts 2 respectively penetrate through the corresponding gaskets 4, nuts 1 are respectively and threadedly connected to the outer surfaces of the threaded bolts 2, and the threaded bolts 2 are respectively and threadedly connected with the adjacent pressure relief valve shell 10 and the adjacent vacuum relief valve shell 11.

An hexagon socket head cap screw 19 is connected between two valve seats 22 and adjacent pressure relief valve housing 10 and vacuum relief valve housing 11 respectively.

The valve of the vacuum relief valve shell 11 is provided with a vacuum end cavity 26, the valve of the pressure relief valve shell 10 is provided with a pressure end cavity 25, and the vacuum end cavity 26 and the pressure end cavity 25 are designed by adopting R-angle correction.

A wire mesh 24 is commonly crimped between the vacuum relief valve housing 11 and the adjacent valve seat insert 23.

The top ends of the two valve disc assemblies are fixedly connected with a first counterweight 13 and a second counterweight 15.

A plurality of connecting bolts 8 are connected between the vacuum relief valve housing 11 and the pressure relief valve housing 10 together, and bolt gaskets 9 are sleeved on the outer surfaces of the connecting bolts 8.

The first valve disc 16 design with the turned down outer edge and the airflow deflector 18 constitute the overall airflow directing arrangement of the valve disc assembly. This arrangement is designed to further lift the valve disc assembly, however maximizing the lift performance of the valve disc assembly does not necessarily improve the overall bleeder performance of the device. We therefore add an airflow deflector 18 which acts to minimize the pressure penalty to the airflow by the first valve disc 16 itself. Achieving the desired relief in the event of a low overpressure.

The first FEP diaphragm 17 and the first valve disc 16 form a seal of the valve disc assembly, the first valve disc 16 being designed with a recessed area of a fixed depth. The purpose is to provide compression compensation for the first FEP diaphragm 17 and the annular valve seat 22. Under the condition of low set pressure and no counterweight, the valve disc assembly only provides effective sealing compression due to insufficient self-gravity.

Embodiment two:

as shown in fig. 6, the two valve disc assemblies comprise a second valve rod 27, the second valve rod 27 is fixedly connected with the guide post 12, a second valve disc 28, a spacing disc 29, a supporting plate 30, a second FEP diaphragm 31, a second compression gasket 32 and a second hexagonal nut 33 are sleeved on the outer surface of the second valve rod 27 from top to bottom in sequence, the second hexagonal nut 33 is in threaded connection with the second valve rod 27, the air deflector 18 abuts against the second FEP diaphragm 31, and the air deflector 18 is fixed at the bottom of the second valve rod 27 through a second screw 34.

The second valve disc 28, spacer disc 29, backing plate 30 and second FEP diaphragm 31 form a seal of the valve disc assembly, the backing plate 30 providing support for the second FEP diaphragm 31 to prevent excessive compression of the second FEP diaphragm 31 per unit area of pressure so that plastic deformation of the second FEP diaphragm 31 occurs. The second valve disc 28 in combination with the spacer disc 29 forms an annular groove providing an effective compression compensation for the combination of the support plate 30 and the second FEP diaphragm 31 at low set pressures.

The depth of the annular groove can be varied by varying the thickness of the spacer disc 29, and the uniform groove depth for the large-sized second valve disc 28 does not fit within a wide pressure setting window. The low set pressure requires a large amount of compression compensation, while the high set pressure can reduce the amount of compression compensation.

The large-sized second valve disk 28, which is stamped from a thin plate, decreases in rigidity with time due to the increase in the size area, and the large-sized second valve disk 28 is provided with a spacer disk 29 for the purpose of compensating rigidity of the second valve disk 28. To prevent the problem of deformation of the second valve disc 28 due to the exposure to momentary overload pressures due to insufficient rigidity.

The foregoing description of the preferred embodiments of the utility model is not intended to limit the utility model to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the utility model are intended to be included within the scope of the utility model.

Claims

1. A pressure vacuum relief valve comprising a vacuum relief valve housing (11), characterized in that: the top fixedly connected with pressure release valve casing (10) of vacuum release valve casing (11), the equal fixedly connected with disk seat (22) in the bottom of vacuum release valve casing (11) and pressure release valve casing (10), two joint has disk seat gasket (23) between disk seat (22) and adjacent vacuum release valve casing (11) and pressure release valve casing (10) respectively, two the equal laminating in top of disk seat (22) is equipped with the valve disc assembly, two air current deflector (18) are all installed to the bottom of valve disc assembly, the top of vacuum release valve casing (11) and the top of pressure release valve casing (10) all are equipped with bonnet shell (3), two the bottom of bonnet shell (3) all butt has vortex cover (5), the top the interior top of vortex cover (5) evenly butt has a plurality of first gag lever (7) between screw thread connection, bottom the interior top of vortex cover (5) evenly butt has a plurality of second gag lever (14), and second gag lever (14) and the top of valve seat (11) all is connected to the guide post (12) between the guide post that slides adjacent between valve casing (11) and the valve casing (12).

2. A pressure vacuum relief valve as claimed in claim 1, wherein: both valve disc assemblies include first valve rod (6), and fixed connection between first valve rod (6) and guide post (12), the surface of first valve rod (6) is from last to overlapping in proper order first valve plate (16), first FEP diaphragm (17), first compress tightly gasket (20) and first hex nut (21), and threaded connection between first hex nut (21) and first valve rod (6), and air deflector (18) offset with first FEP diaphragm (17), air deflector (18) are fixed in the bottom of first valve rod (6) through first screw.

3. A pressure vacuum relief valve as claimed in claim 1, wherein: both valve disc assemblies include second valve rod (27), and fixed connection between second valve rod (27) and guide post (12), the surface of second valve rod (27) is from last to being equipped with second valve plate (28), spacer disc (29), backup pad (30), second FEP diaphragm (31), second compress tightly gasket (32) and second hexagon nut (33) in proper order down, and threaded connection between second hexagon nut (33) and second valve rod (27), and air deflector (18) offset with second FEP diaphragm (31), air deflector (18) are fixed in the bottom of second valve rod (27) through second screw (34).

4. A pressure vacuum relief valve as claimed in claim 1, wherein: the bottom of two valve gap casing (3) has all pressed fit packing ring (4), two valve gap casing (3) respectively with be connected with a plurality of screw bolts (2) jointly between adjacent pressure relief valve casing (10) and the vacuum relief valve casing (11), and screw bolt (2) run through corresponding packing ring (4) respectively, a plurality of the surface of screw bolt (2) is all threaded connection has nut (1), and a plurality of screw bolts (2) respectively with adjacent pressure relief valve casing (10) and vacuum relief valve casing (11) between threaded connection.

5. A pressure vacuum relief valve as claimed in claim 1, wherein: and the two valve seats (22) are respectively connected with an inner hexagon bolt (19) together with the adjacent pressure relief valve housing (10) and the vacuum relief valve housing (11).

6. A pressure vacuum relief valve as claimed in claim 1, wherein: a vacuum end cavity (26) is formed at the valve of the vacuum relief valve shell (11), a pressure end cavity (25) is formed at the valve of the pressure relief valve shell (10), and R angle correction designs are adopted for the vacuum end cavity (26) and the pressure end cavity (25).

7. A pressure vacuum relief valve as claimed in claim 1, wherein: a wire mesh (24) is commonly pressed between the vacuum relief valve shell (11) and the adjacent valve seat gasket (23).

8. A pressure vacuum relief valve as claimed in claim 1, wherein: the top ends of the two valve disc assemblies are fixedly connected with a first counterweight (13) and a second counterweight (15).

9. A pressure vacuum relief valve as claimed in claim 1, wherein: a plurality of connecting bolts (8) are connected between the vacuum relief valve shell (11) and the pressure relief valve shell (10), and bolt gaskets (9) are sleeved on the outer surfaces of the connecting bolts (8).