Use these valves for emergency relief for liquids, gases or clean steam where pressures must be relieved quickly to reduce damage that could result from overpressure in a system. Where the overpressure needs to be controlled more gradually, such as in back pressure or pump bypass applications use our Backpressure valves which will reduce the probability of pressure spikes that often occur when relief valves are selected for pressure control applications. Valve should only be used selectively where the materials chosen are compatible with the fluid used and will not cause corrosive buildup or crystallization in the close clearances between the piston and body bore, which could keep the poppet from opening freely. Use only clean, strained, or filtered liquids or gases so that the valve can operate without buildup of debris or solid matter which can cause the valve to malfunction. A strainer or filter with the appropriate perf or mesh and pressure rating can be purchased from Straval. Apply only where the discharge piping is not subjected to a high back pressure, as this may affect the relief setting. If the back pressure is steady or constant, compensating for the change in set pressure can be simply made by readjusting the spring load, or by using a different spring selection, or selecting a different valve type designed for this.
Features & Benefits
- Body: Standard material is 316 Stainless Steel. For non sanitary applications 303SS is offered.
- Poppet: Also available in the same materials as the body. Teflon is available for low pressure service (<150 PSI) and where required tighter seat shutoff and for gases.
- Elastomeric piston seal: Choice of different elastomers including Teflon expands valve usage to a wide range of applications and fluids. Choice of elastomer determines final temperature limitation.
- Spring chamber: This part is non-wetted, the standard construction is a 303 Stainless Steel or 316 Stainless Steel.
- Right-angle porting: Standard construction is bottom inlet, side outlet.
- Internal surfaces: 20RA is standard with electro-polishing available as an option