Wafer Type NRV
Wafer Type NRV
-Wafer type non- return valve, it is a check valve, here refering to following types of wafer check valve:
- Non slam check valve
- Dual plate check valve
- Single disc check valve
A wafer type NRV is usually installed between two flanges and fixed with bolts. It has a compact structure and is easy to install. It is an automatic valve that opens and closes relying on the pressure of the medium and is typically used in small and medium-sized pipeline systems. Its main function is to prevent the backflow of the medium.
Made with the proper materials, it can be applied to a variety of media such as water, steam, oil products, nitric acid, acetic acid, strongly oxidizing media, and uric acid.
Topwells’ wafer type NRV has following features:
- Its dual plate design adopts an internal retention fitting. The fitting does not interfer the gasket sealing surface, to ensure the effective seal between valve and pipeline;
- The dual plate wafer design makes this check valve much lighter, which is only 10~25% of the weight of conventional swing check valve, to save money in valve cost and reduce the installation cost;
- The spring feature aids in keeping the valve closed and the lighter weight with less pipeline bending loads make the valve suitable in any position flexibly, which allows you to design your piping layout in the most efficient and more economical method;
- When the valve opens, the heel of the dual plate is lifted in the direction of the flow, to avoid that the heel drag across the seating surface and cause wear. When closing the valve, both the two high torsion springs and the back pressure will force disc toe and heel back in turn to the flat seat to complete the seal.
- They do not allow backward flow. Once any flow attempts to reverse, the valve closes immediately.
- They have higher efficiency because their pressure drop is minimal.
- Wafer-type non-return valves are designed to maintain working fluid pressure.
- These valves are easy to install, repair, and clean.
- They are free from fluid leakage.
- Wafer-type non-return valves can relieve the water hammer and its related effects.
- They are light in weight in regard of other non-return valves.
- These valves can be installed in either horizontal or vertical positions since they do not depend only on gravity to prevent backward flow.
- Wafer type NRV are fasting acting comparing to other valves such as globe valves.
Technical Specifications
| Single Disc Check Valve | API 594 / API 6D |
| Non Slam Check Valve | API 594 |
| Dual Plate Check Valve | API 594 |
| Flanged End Dimensions | ASME B16.5, ASME B16.47 A & B |
| Valve Inspection & Testing | API 598 |
| Visual Inspection | MSS SP 55 |
| Non Destructive Test (RT, UT, MT, PT) | ASME B16.34 |
| Pressure – Temperature Rating | ASME B16.34 |
| BODY | CI IS 210 GR FG 200/220/CS ASTMA 216 GR WCB /SG IRON/ CF8/SS 304 / CF8M/SS 316 /CF3/CF3M/GUN METAL/ALUMINIUM |
| PIN | MS/AISI 304/ AISI 316 |
| RINGS | NBR/NEOPRENE /NITRILE /SILICON/ VITON/PTFE/STL/INTREGAL |
| SIZE RANGE | 25NB TO 1200 NB (1″ TO 48″) |
| PRESSURE CLASS | 150# to 1500# |
The data is for reference only, please consult andy@vokkan.com for details.
- Steam
- Hot & cold water
- Power & heat engineering
- Pressurized Air
- Industrial technologies
- Fluids without acidity or alkalinity properties
What is wafer type NRV?
Wafer type NRV means wafer type non return valve.
The non return valve opens and closes automatically driving by the flow of the medium itself. Just as its name indicating, it allows only one direction flowing, and can prevent the reverse flow and force it runs back again into the system, thus can also prevent the reverse rotation of the pump and the driving motor, as well as the release of the medium in the container.
The reason why the wafer type NRV is called “wafer type” is because of its installation method. The “wafer type” is usually installed between two flanges and fixed with bolts. This structure makes the valve clamp between the flanges of the pipeline like a clip, hence the name “wafer type NRV”.
What is NRV and its types?
NRV means non-return valve.
Non-return valves can be categorized by different methods. In a simple way, they are devided into three common types by structures: lift non-return valves, swing non-return valves, and butterfly non-return valves.
ENQUIRY
