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Wafer type dual plate check valve: metal seated vs resilient seated

Wafer dual plate check valve is used for pure pipelines and industrial, environmental protection, water treatment, high-rise building water supply and drainage pipelines, to prevent the reverse flow of the medium. The check valve adopts a clamp type, the butterfly plate is two semicircles, and it adopts a spring for forced reset. The sealing surface can be built-up welding wear-resistant material or rubber lining, with a wide range of use and reliable sealing.

The check valve opening and closing parts are opened or closed automatically by the flow and force of the medium to prevent the medium from flowing back. The valve is called the check valve. Check valves belong to the category of automatic valves, which are mainly used in pipelines where the medium flows in one direction, and only allow the medium to flow in one direction to prevent accidents.

According to the structure of the check valve, it can be divided into three types: lift check valve, swing check valve and butterfly check valve. Lift check valves can be divided into two types: vertical and horizontal. Swing check valves are divided into three types: single valve, double valve and multi valve. The butterfly check valve is a straight-through type. The above-mentioned check valves can be divided into three types in connection form: threaded connection, flange connection and welding. A check valve is a valve that can automatically prevent fluid from flowing back. The disc of the check valve is opened under the action of fluid pressure, and the fluid flows from the inlet side to the outlet side. When the pressure on the inlet side is lower than that on the outlet side, the valve flap is

H46-double flanged dual plate check valve-metal seated

H46-double flanged dual plate check valve-metal seated

automatically closed under the action of the fluid pressure difference, its own

lug type dual plate check valve metal seated (3)

lug type dual plate check valve metal seated (3)

gravity and other factors to prevent the fluid from flowing back.

klug type dual plate check valve metal seated (1)The dual plate check valve is divided into flange dual plate check valve, lug dual plate check valve and wafer dual

plate check valve.

Classification of wafer dual plate check valves: hard-seal wafer dual plate check valve and soft-seal wafer dual plate check valve; of which soft-seal wafer check valve is divided into full-lined soft-seal wafer check valve and Semi-lined/normal soft-seal wafer dual plate check valve.

Features of Wafer dual plate Check Valve:

  1. Simple structure and light weight, especially suitable for low-pressure large-diameter pipelines;
  2. The paired clamp connection mode, the production process is simple, and the disassembly and assembly are convenient;
  3. The check valve adopts the clamp type, the butterfly plate is two semicircles, and the spring is forced to reset. The sealing surface can be built-up welding wear-resistant material or rubber lining, with a wide range of use and reliable sealing.

Model: H76X/H76H/H76W
Name: Wafer dual plate check valve
Please refer to the main technical parameters and spare parts materials:
https://www.tanghaivalve.com/wafer-type-double-disc-swing-check-valve-introduction/
Product name: Wafer double plate check valve (soft seal)
National Standard Number: H76X

dual plates check valve photos-normal sealing (1)

dual plates check valve photos-normal sealing (1)

Size range: DN40-DN1200
Pressure rating: PN10/16/25/40/64/100
Valve features: double valve plate design, short running track of the valve plate, spring load makes the valve plate close more quickly, effectively preventing water hammer
When the valve plate is opened, it is close to 90 degrees, and the pressure loss is small
Zero leakage
Size range: 2″ to 48″
Pressure range: 10bar-50 bar
Suitable flange: National standard or EN1092 PN10/PN16/PN25/PN40 or ANSI 125/150/300
Structure length: EN558 series 16, API594

Body material: gray cast iron, ductile iron, carbon steel, stainless steel, aluminum bronze
Valve plate material: ductile iron nickel-plated, stainless steel 201, stainless steel 304,

dual plates check valve photos- full rubber

dual plates check valve photos- full rubber

stainless steel 316, aluminum bronze
Valve seat material: nitrile NBR, EPDM, oil and acid and alkali resistant fluorine rubber VITON-A, steam resistant fluorine rubber VITON-B, hard seal
Uses: Suitable for installation at the outlet of high-lift pumps, or as a bottom valve in front of the pump, suitable for water, sea water, steam, oil, chemicals, chlorine, oxygen, and steam. Can be installed horizontally or vertically.
Application scope:
It is suitable for industrial, environmental protection, sewage treatment, high-rise building water supply and drainage pipelines, etc. It can also be used for environmental systems with corrosive media such as power plants and steel plants gypsum slurry.

 

Product name: Wafer double plate check valve (metal seated)
National standard number: H76H(W)-16C(16P, 16R, 16RL)
Size range: DN40-DN1200

H76-wafer type dual plate check valve metal seated

H76-wafer type dual plate check valve metal seated

Pressure rating: PN10/16/25/40/64/100
Temperature range: -20℃ -350℃
Body material: WCB, A105, CF8, CF3, CF8M.CF3M and other materials and special steel
Valve plate material: WCB, A105.2CR13, 304.304L.316.316L and other materials and special steel
Valve shaft material: A105.2CR13, 304.304L.316.316L and other materials and special steel
Valve seat material: 2CR13, 304.304L.316.316L, STL and other materials and special steel
Application range: water, steam, oil, nitric acid, acetic acid, strong oxidizing medium and urea and other media
More video for wafer dual plate check valve, please see below:
https://www.youtube.com/watch?v=pGrkznOd-JA
https://youtu.be/etwT8RX-S3Q
https://www.youtube.com/watch?v=XqRRI7o-LFI

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Related news/knowledge:

All types of check valve and its structures

Check valve refers to a valve whose opening and closing parts are circular discs and rely on its own weight and medium pressure to generate actions to block the back flow of the medium. It is an automatic valve, also known as one-way valve, non-return valve(NSV) or isolation valve. The movement of the disc is divided into lift type and swing type. The lift check valve is similar in structure to the shut-off valve, but lacks the valve stem that drives the disc. The medium flows in from the inlet end (lower side) and flows out from the outlet end (upper side). When the inlet pressure is greater than the sum of the weight of the disc and its flow resistance, the valve is opened. On the contrary, the valve is closed when the medium flows back. The swing check valve has a disc that is inclined and can rotate around the axis, and the working principle is similar to that of the lift check valve. The check valve is often used as the bottom valve of the pumping device to prevent the backflow of water. The combination of check valve and stop valve can play a role of safety isolation. The disadvantage is that the resistance is large and the sealing performance is poor when closed.

all types of check valve and structures -code names-photos

all types of check valve and structures -code names-photos

The working principle of the check valve:
Check valves can also be used to supply pipelines for auxiliary systems where the pressure may rise above the system pressure. Check valves can be divided into swing check valves (rotating according to the center of gravity) and lift check valves (moving along the axis).

The function of this type of check valve is to only allow the medium to flow in one direction and prevent the flow in the opposite direction. Usually this kind of valve works automatically. Under the action of the fluid pressure flowing in one direction, the valve flap opens; when the fluid flows in the opposite direction, the fluid pressure and the self-coincidence of the valve flap act on the valve seat, thereby cutting off the flow.

Among them, the check valve belongs to this type of valve, which includes swing check valve and lift check valve. The swing check valve has a hinge mechanism and a valve disc like a door that rests freely on the inclined valve seat surface. In order to ensure that the valve clack can reach the proper position of the valve seat surface every time, the valve clack is designed in a hinge mechanism so that the valve clack has enough space for rotation and makes the valve clack truly and comprehensively contact the valve seat. The valve clack can be made of metal, leather, rubber, or synthetic covering can be inlaid on the metal, depending on the performance requirements. When the swing check valve is fully opened, the fluid pressure is almost unimpeded, so the pressure drop through the valve is relatively small. The valve disc of the lift check valve is located on the sealing surface of the valve seat on the valve body. Except that the disc can be raised and lowered freely, the rest of the valve is like a shut-off valve. The fluid pressure lifts the disc from the seat sealing surface, and the backflow of the medium causes the disc to fall back onto the seat and cut off the flow. According to the conditions of use, the valve clack can be an all-metal structure, or it can be in the form of a rubber pad or a rubber ring inlaid on the valve clack frame. Like a shut-off valve, the passage of fluid through the lift check valve is also narrow, so the pressure drop through the lift check valve is larger than that of the swing check valve, and the flow rate of the swing check valve is restricted. Rarely.
Classification of check valves:
The valve that opens or closes on its own by the force of the flow of the medium to prevent the medium from flowing back is called a check valve. Check valves belong to the category of automatic valves, which are mainly used in pipelines where the medium flows in one direction, and only allow the medium to flow in one direction to prevent accidents.

Classified by structure:
According to the structure, it can be divided into three types: lift check valve, swing check valve and butterfly check valve:

1. Lift check valves are divided into two types: vertical and horizontal.

2. The swing check valve is divided into three types: single, double and multiple.

3. The butterfly check valve is a straight-through type.

The above check valves can be divided into four types in connection form: threaded connection, flange connection, welding connection and wafer connection.

The selection criteria of the check valve are as follows:

1. In order to prevent the medium from flowing back, check valves should be installed on the equipment, devices and pipelines;

2. Check valves are generally suitable for clean media, not for media containing solid particles and high viscosity;

3. Generally, horizontal lift check valves should be used on horizontal pipes with a nominal diameter of 50mm;

4. The straight-through lift check valve can only be installed in horizontal pipelines;

5. For the inlet pipeline of the water pump, a bottom valve should be used. The bottom valve is generally only installed on the vertical pipeline at the inlet of the pump, and the medium flows from bottom to top;

6. Compared with the swing type, the lifting type has better sealing performance and greater fluid resistance. The horizontal type should be installed on the horizontal pipeline, and the vertical type on the vertical pipeline;

7. The installation position of the swing check valve is not restricted. It can be installed on a horizontal, vertical or inclined pipeline. If installed on a vertical pipeline, the flow direction of the medium should be from bottom to top;

8. The swing check valve should not be made into a small-diameter valve, it can be made into a high working pressure, the nominal pressure can reach 42MPa, and the nominal diameter can also be large, the maximum can reach more than 2000mm. According to the different materials of the shell and the sealing parts, it can be applied to any working medium and any working temperature range. The medium is water, steam, gas, corrosive medium, oil, medicine, etc. The working temperature range of the medium is between -196–800℃;

9. The applicable occasion for swing check valve is low pressure and large diameter, and the installation occasion is restricted;

10. The installation position of the butterfly check valve is not restricted. It can be installed on a horizontal pipeline, or on a vertical or inclined pipeline;

11. Diaphragm check valve is suitable for pipelines that are prone to water hammer. The diaphragm can eliminate the water hammer caused by the reverse flow of the medium. It is generally used on low-pressure and normal temperature pipelines, and is especially suitable for tap water pipelines. Normal media work The temperature is between -12-120℃, and the working pressure is less than 1.6MPa, but the diaphragm check valve can achieve a larger diameter, and the maximum DN can reach more than 2000mm;

12. The spherical check valve is suitable for medium and low pressure pipelines and can be made into a large diameter;

13. The shell material of the spherical check valve can be made of stainless steel, and the hollow sphere of the seal can be wrapped with polytetrafluoroethylene engineering plastic, so it can also be applied to the pipeline of general corrosive media, and the working temperature is -101–150 Between ℃, its nominal pressure is ≤4.0MPa, and the nominal passage range is between DN200-DN1200;

14. When selecting check valves for incompressible fluids, the required closing speed must be evaluated first, and the second step is to select the type of check valve that may meet the required closing speed;

15. The check valve for compressible fluid can be selected according to the similar method of check valve for incompressible fluid. If the medium flow range is large, the check valve for compressible fluid can be used A deceleration device, if the medium flow is stopped and started quickly and continuously, such as the outlet of the compressor, a lift check valve is used;

16. The corresponding size of the check valve should be determined, and the valve supplier must provide the data of the selected size, so that the valve size when the valve is fully opened at a given flow rate can be found;

17. For high and medium pressure check valves below DN50mm, vertical lift check valves and straight-through lift check valves should be used;

18. For low-pressure check valves below DN50mm, butterfly check valves, vertical lift check valves and diaphragm check valves should be used;

19. For high and medium pressure check valves with DN greater than 50mm and less than 600mm, swing check valves should be used;

20. For medium and low pressure check valves with DN greater than 200mm and less than 1200mm, wear-free spherical check valves should be used;

21. For low pressure check valves with DN greater than 50mm and less than 2000mm, butterfly check valves and diaphragm check valves should be used;

22. For pipelines that require relatively small water hammer impact or no water hammer when closed, slow-closing swing check valves and slow-closing butterfly check valves should be selected.

Types of check valves we produce:

We have other types of check valves: single-disc swing check valvedual plate check valve, tilting disc swing check valvelift swing check valvesilent check valve and ball check vlave used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D,

Installation method and precautions of check valve

Check valve installation method:
1. Swing check valve: The disc of the swing check valve is disc-shaped and rotates around the shaft of the valve seat

double-wing-check-valve-3

double-wing-check-valve-3

passage. Because the inner passage of the valve is streamlined, the flow resistance is smaller than that of the lift check valve. It is suitable for large-caliber occasions where the flow rate is low and the flow does not change frequently, but it is not suitable for pulsating flow, and its sealing performance is not as good as the lifting type. Swing check valves are divided into three types: single, double and multiple valves. These three types are mainly classified according to the valve diameter. The purpose is to prevent the medium from stopping or flowing backwards and weaken the hydraulic shock.

Silent check valve

2. Lifting check valve: a check valve whose disc slides along the vertical centerline of the valve body. The lifting check valve can only be installed on a horizontal pipeline. The disc can be used on a high-pressure small-diameter check valve. . The valve body shape of the lift check valve is the same as the stop valve (can be used in common with the stop valve), so its fluid resistance coefficient is relatively large. Its structure is similar to the stop valve, and the valve body and disc are the same as the stop valve. The upper part of the valve disc and the lower part of the valve cover are processed with guide sleeves. The disc guide can be lifted and lowered freely in the valve guide sleeve. When the medium flows downstream, the disc opens by the thrust of the medium. When the medium stops flowing, the disc depends on its own It falls on the valve seat to prevent the medium from flowing backward. The direction of the medium inlet and outlet channel of the straight-through lift check valve is perpendicular to the direction of the valve seat channel; the vertical lift check valve has the same direction of the medium inlet and outlet channels as the valve seat channel, and its flow resistance is smaller than that of the straight-through type.

3. Disc check valve: a check valve with the disc rotating around the pin shaft in the valve seat. The disc check valve has a simple structure and can only be installed on a horizontal pipeline, with poor sealing performance.

4. In-line check valve: a valve with the valve flap sliding along the centerline of the valve body. In-line check valve is a new type of valve. It is small in size, light in weight, and good in processing technology. It is one of the development directions of check valves. However, the fluid resistance coefficient is slightly larger than that of the swing check valve.

5. Compression check valve: This valve is used as a boiler feed water and steam shut-off valve. It has a comprehensive function of lift check valve and stop valve or angle valve.

In addition, there are some check valves that are not suitable for pump outlet installation, such as bottom valve, spring type, Y type, etc.

Precautions
1. Do not allow the check valve to bear weight in the piping system. Large check valves should be independently supported so that they are not affected by the pressure generated by the piping system.

2. When installing, pay attention to the direction of medium flow should be consistent with the direction of the arrow marked on the valve body.

3. Lifting vertical flap check valve should be installed on the vertical pipeline.

4. Lifting horizontal flap check valve should be installed on the horizontal pipeline.

Related news /products:
All types of check valve and its structures;
Valve installation instructions and process precautions;
Daily maintenance and precautions of ball valves
Introduction of cast steel lift swing check valve;