WITT is a manufacturer of Pressure relief valves /Safety relief valves for technical gases. They are designed to protect against overpressure by discharging pressurized gases and vapors from pipelines, pressure vessels and plant components. Pressure relief valves (PRV) or safety relief valves (SRV) are often the last line of defense against explosion – and such an explosion could be fatal. Other common names for pressure relief valves are safety relief valve, safety valve, pressure safety valve, overpressure valve or just relief valve.
What are the benefits of WITT pressure relief valves?
WITT safety or pressure relief valves are very precise. They are individually preset to open at a predetermined pressure within the range 0.07 to 652 Psi. Their small size and orientation-independent installation allow a wide range of connection options. WITT pressure relief valves also stand out due to their high blow-off flow rates of up to 970m³/h. They can be used within a temperature range of -76° F to +518°F and even with very low pressures.
These very low pressure valves can also be used in reverse, to maintain a constant gas pressure in a vessel, very accurately and very reliably.
TÜV-tested safety relief valves
For maximum safety, WITT undertakes 100 % testing of each safety relief valve before it is delivered. In addition, WITT offers individual testing of each pressure relief valve by the TÜV, with their certificate as proof of the correct set pressure.
How do pressure relief valves work?
WITT safety relief valves are direct-acting, spring-loaded valves. When the preset opening pressure is reached, a spring-loaded element in the valve gives way and opens, and the pressure is relieved. Once the pressures are equalized, the valve closes automatically and can be reactivated any time the pressure rises again. Depending on the application and the nature of the gas, the safety relief valves can either discharge to atmosphere, or via a connected blow-off line. The opening pressure of the safety valves is preset by WITT at the factory according to the customer’s requirements.
Applications for pressure relief valves
Pressure relief valves are used in numerous industries and industrial applications where, for example, gases pass through pipelines or where special process vessels have to be filled with gas at a certain pressure.
These include, among other things:
- Pipeline, plant and container construction
- Industrial furnace construction
- Insulators and reactors (e.g. “glovebox” systems)
- hydrogen-powered vehicles
- Additive manufacturing (3D printer)
What materials are safety relief valves made of?
For most industrial applications using technical gases, brass is usually the standard material of construction of the safety relief valve body/housing. For the use of pressure relief valves with aggressive and corrosive gases, the housings are made of high-quality stainless steel (1.4541/AISI 321, 1.4404/AISI 316L, 1.4305/AISI 303 or 1.4571/AISI 316Ti). The use of aluminium as a housing material is also possible.
Depending on the type of gas used and individual customer requirements, various sealing materials and elastomers are available to ensure the safety of your systems under even the most difficult conditions.
What connections do pressure relief valves have?
WITT pressure relief valves are available with different connections. In addition to the standard versions with the usual internal or external threads, special versions with KF or CF flanges, VCR or UNF threads can also be ordered. Special adapters for connecting the safety relief valve to a blow-off line are also available.
Practical Example: Pressure Relief Valves in Additive Manufacturing