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Purge Valve

Swagelok® Relief Valves

Swagelok® proportional relief valves provide overpressure protection in general industrial applications with a variety of set pressures available. Bleed and purge valves provide effective bleeding, venting, or draining of signal line pressure to atmosphere.

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Swagelok® R series proportional relief valves open gradually as pressure increases, providing simple, reliable overpressure protection, protecting workers, and helping to maintain proper process conditions. Set pressures can be configured at the factory or easily adjusted in the field to suit changing operating conditions. Swagelok® RV series medium-pressure relief valves can be used in applications with operating pressures up to 20 000 psig (1378 bar).

Swagelok® PRV series proportional safety relief valves are certified to PED 2014/68/EU Category IV and CE-marked in accordance with the Pressure Equipment Directive as a safety valve according to ISO-4126-1. They are factory-set, tested, locked, and tagged with the set pressure.

Swagelok® BV series bleed valves can be used on instrumentation devices such as multivalve manifolds or gauge valves to allow safe removal of instruments and to assist in the calibration of control devices. They are available with low emission (Low-E) certification according to API 624 to combat fugitive emissions.

Swagelok® P series purge valves are manual bleed, vent, or drain valves. Knurled caps are permanently assembled to valve bodies for safety, and both bleed and purge valves are compact for convenient installation.

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Relief Valve Categories

Bleed and Purge Valves, BV and P Series

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.

Medium-Pressure Relief Valves, RV Series

Medium-Pressure Relief Valves, RV Series

Ensure over-pressure protection in general-industry applications with set or adjustable pressure and lock nut for stability.

Proportional Relief Valves, R3, R4, RL3, and RL4 Series

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.

Proportional Safety-Relief Valves, PRV Series

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.

Spare Parts and Accessories

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.

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

Calculate Flow Rate for the Right Valve Selection

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

Learn how to apply the practical STAMPED method to select the valves most suited to your industrial fluid or sampling system design applications.

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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.

Block valves in an industrial fluid system
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.

Cleanroom assembly of a Swagelok ALD20 UHP valve for semiconductor industry use
One New Valve. Three Reasons It Could Change Semiconductor Manufacturing

Find out how the latest innovation in atomic layer deposition (ALD) valve technology is changing the game for high-tech semiconductor manufacturers.

Relief and Bleed 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. PRV series proportional safety relief valves are certified safety valves with five set spring pressure ranges are available with the selected set pressure factory-set, tested, locked, and tagged to ensure the desired setting.

Bleed and Purge Valves

Swagelok bleed valves can be used 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.

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