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Purge Valve

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.

Relief Valves Catalogs

Locate detailed product information, including materials of construction, pressure and temperature ratings, options, and accessories.

Swagelok flow coefficient (C<sub>v</sub>) calculator for valves

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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Swagelok Resources Curated for You

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How to Select the Right Valves for Your Industrial Fluid System

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Minimize the Costs of Fugitive Emissions with Low-E Valves

Fugitive emissions are a growing concern in the chemical and petroleum refining industry. Certified low-emissions (Low-E) valves can protect your facility and bottom line. Learn what they are, how they are tested, and how they can help you in this post.

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How to Isolate Industrial Fluid Systems with Block Valves

The isolation of industrial fluid system lines prior to maintenance is vital to plant safety. One of the safest ways to isolate a fluid system line is to install two block valves. Learn how to design proper configurations for your system.

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Relief and Bleed Valves

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.