A piston-type safety relief valve is a device that relieves pressure mechanically. Its principle is to control the pressure inside the pressure vessel by adjusting the valve's opening and closing pressures. When the pressure exceeds a set value, the valve automatically opens, releasing the excess pressure to prevent overpressure within the pressure vessel.
Technical Parameters
- Standards: Design and manufacturing comply with API 526 (Standard for Steel Safety Relief Valves), ASME BPVC (Boiler and Pressure Vessel Code), and ANSI B16.34 (Valve Dimensions and Pressure/Temperature Ratings); Filtration performance complies with ISO 4028 (Hydraulic Filter Element Testing Standard); Sealing performance complies with ANSI B16.104.
- Nominal pressure: Standard sizes PN10-PN42 (corresponding to Class 150-Class 2500), low-pressure models PN10-PN16 are suitable for municipal water supply and low-pressure circulating water systems, medium- and high-pressure models PN25-PN42 are suitable for industrial high-pressure pipelines (such as hydraulic systems and chemical solvent transportation); the valve body's maximum withstand pressure is 1.5 times the nominal pressure to ensure structural safety in case of system overpressure.
- Nominal diameter: Mainstream sizes DN25-DN300. Small diameter models (DN25-DN80) are suitable for branch pipes and equipment inlets/outlets (such as pump outlets and heat exchanger inlets). Medium diameter models (DN100-DN200) are suitable for main pipes and workshop water supply systems. Large diameter models (DN250-DN300) are suitable for municipal main pipes and large industrial circulating water systems. Large diameter models adopt a double-piston synchronous opening design to ensure uniform force distribution during pressure relief. The valve body wall thickness is ≥20mm (carbon steel/stainless steel material) to prevent deformation caused by the weight of the large diameter pipe.
- Operating temperature: Divided into several ranges depending on the material and sealing material-Carbon steel + EPDM seal is suitable for -10℃-80℃ (ordinary tap water, cooling water); stainless steel + PTFE seal is suitable for -20℃-120℃ (hot water, mildly corrosive fluids); high-temperature model (316L + metal hard seal) is suitable for -29℃-450℃ (high-temperature steam, hot oil); low-temperature antifreeze model (with heat tracing) is suitable for -30℃-80℃ (cold northern regions).
- Valve body and internal components materials: Valve body materials include WCB carbon steel, 304 stainless steel (CF8), and 316L stainless steel (CF8M); filter element materials are 304/316L stainless steel braided mesh (filtration accuracy 0.1-1mm) and sintered stainless steel filter element (high-precision filtration); piston valve core material is 304/316L stainless steel (surface hardened treatment); spring material is stainless steel (304/316), with a fatigue life ≥100,000 cycles (pressure relief cycle); sealing materials include PTFE, EPDM, fluororubber, and metal hard seals.
- Performance parameters: Opening pressure setting range: 0.1MPa-4.0MPa; Opening pressure accuracy: ±2% (set pressure value); Pressure relief response time: 0.1-0.3 seconds (when pressure exceeds the set value by 10%); Maximum pressure relief: DN100 model ≥200m³/h (ΔP=0.5MPa), DN200 model ≥500m³/h (ΔP=0.5MPa); Closing leakage meets ANSI B16.104 Class VI standard (≤0.01cm³/min for DN100 and below under normal temperature and pressure); Filtration accuracy: 0.1mm, 0.5mm, 1mm (optional).
- Applicable Media: Covers clean water (tap water, drinking water), industrial circulating water (containing small amounts of impurities), mildly corrosive fluids (such as dilute brine, ethanol solution, pH 4-10), hot water (≤120℃), low-viscosity oils (lubricating oil, diesel oil, viscosity ≤50cSt), and chemical solvents (such as methanol, ethylene glycol); Not suitable for strongly corrosive media (such as concentrated hydrochloric acid, concentrated nitric acid), fluids containing large particulate impurities (particle size >1mm), or high-viscosity fluids (viscosity >100cSt), to avoid filter element clogging or valve core jamming.
- Connection Method: Supports flange connection (compliant with ANSI B16.5, DIN 2501, sealing surface type RF/RTJ); some small diameter models (DN25-DN50) can be equipped with threaded connection (NPT/G thread); it is recommended to use a flanged silencer or pressure relief pipe at the pressure relief end; flange sealing surface roughness Ra≤3.2μm, compatible with rubber gaskets, graphite gaskets, and metal spiral wound gaskets.
Application Scenarios of Piston-Type Safety Relief Valves
Piston-type safety relief valves are widely used in various pressure vessels, such as boilers, compressors, and storage tanks. These devices play a vital role in industrial production, but excessive internal pressure can pose a threat to equipment and personnel. Therefore, using stainless steel piston-type safety relief valves can ensure the safety of equipment and personnel.
Advantages and Features of Piston-Type Safety Relief Valves
1. Safe and Reliable: Stainless steel piston-type safety relief valves are carefully designed and optimized to ensure the safety of equipment and personnel.
2. High Efficiency and Energy Saving: This equipment can effectively reduce energy consumption and improve production efficiency.
3. Long Service Life: Stainless steel has excellent corrosion resistance and wear resistance, ensuring a long service life for the equipment.
4. Easy Maintenance: Stainless steel piston-type safety relief valves have a simple structure and are easy to maintain, requiring minimal investment of manpower and resources.
Piston Type Safe Pressure Relief Valve Factory
