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Swagelok® Relief Valves
Proportional relief valves provide overpressure protection with a variety of set pressures available. For applications needing to drain signal line pressure to atmosphere, bleed and purge valves will manually bleed, vent, or drain that pressure.
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Bleed and Purge Valves, BV and P Series
Experience convenient installation with compact bleed valves for instrumentation devices and purge valves, such as manual bleed, vent, or drain valves.
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Medium-Pressure Relief Valves, RV Series
Ensure over-pressure protection in general-industry applications with set or adjustable pressure and lock nut for stability.
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Proportional Relief Valves, R3, R4, RL3, and RL4 Series
Discover high- and low-pressure proportional relief valves that open gradually as pressure increases. Suitable for liquid or gas service.
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Proportional Safety-Relief Valves, PRV Series
Provides flexible, reliable over-pressure protection, certified under PED 2014/68/EU Category IV, and CE-marked according to ISO-4126-1.
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Spare Parts and Accessories
Find spare parts and accessories for relief valves, including spring kits, seal kits, handle kits, insert kits, and poppet kits for optimal performance.
Relief Valves Catalogs
Locate detailed product information, including materials of construction, pressure and temperature ratings, options, and accessories.
Features: Gas and liquid service; Working pressure: 6000 psig (413 bar); Set pressures from 145 to 6000 psig (10.0 to 413 bar); All 316L stainless steel construction; 1/4 through 1 in. NPT and ISO/BSP parallel thread end connections; Certified to PED 97/23/EC Category IV
Bleed Valves: Working pressures up to 10 000 psig (689 bar); Temperatures up to 850°F (454°C); 316 stainless steel, carbon steel, alloy 400, or alloy C-276 materials. Purge Valves: Working pressures up to 4000 psig (275 bar); Temperatures up to 600°F (315°C); 316 stainless steel, brass, or carbon steel materials
Features: Liquid or gas service; Set pressures from 10 to 6000 psig (0.68 to 413 bar); 1/4 and 1/2 in. and 6 to 12 mm end connections
Swagelok offers pressure-reducing, back-pressure, dome-loaded, and spring-loaded pressure regulators to control pressure and minimize droop in instrumentation systems.
Swagelok® offers medium- and high-pressure fittings, tubing, valves, and related accessories with temperatures up 1000°F (537°C), pressure ratings up to 60 000 psig (4134 bar) in sizes ranging from 1/4 to to 1 in. for medium-pressure products and 1/4 to 9/16 in. for high-pressure products. NACE® MR0175/ISO15156 compliance is available.
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The Right Valve Can Make All the Difference
Use our valve flow coefficient (Cv) calculator to chose a valve sized correctly for your needs.
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How to Select the Right Valves for Your Industrial Fluid System
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Proportional Relief, Bleed, and Purge Valves
Proportional Relief Valves
R series proportional relief valves provide simple, reliable, overpressure protection for a variety of liquid or gas general-industry applications with set pressures from 10 to 6000 psig (0.7 to 413 bar). They open gradually as the pressure increases and will close when the system pressure falls below the set pressure. The set pressure can be set at the factory or easily adjusted in the field. PRV series proportional safety relief valves are certified to PED 2014/68/EU Category IV, CE-marked in accordance with the Pressure Equipment Directive as a safety valve according to ISO-4126-1, and factory-set, tested, locked, and tagged with the set pressure.
Bleed and Purge Valves
Swagelok bleed valves can be used on instrumentation devices such as multivalve manifolds or gauge valves to vent signal line pressure to atmosphere before removal of an instrument or to assist in calibration of control devices. Male NPT and SAE end connections are available. Purge valves are manual bleed, vent, or drain valves with NPT, SAE, Swagelok tube fitting, or tube adapter end connections. A knurled cap is permanently assembled to the valve body for safety. Both bleed and purge valves are compact for convenient installation.