External pressure relief valves for LPG overpressure protection

External pressure relief valves are designed to be primary relief valves on LPG/NH3 tanks, ASME containers above and below ground, bulk plant installations and skid tanks, as well as their connecting piping. They provide an added security for people and equipment where overpressure can accumulate and cause disasters.

Product description

These relief valves are cost-efficient safety devices that due to their small size allow for installation where space is limited. As they are fully external, added protection is needed to prevent damage on the devices.

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Body: Brass, aluminium rod, upper cold rolled steel, lower ductile iron
Liner: Stainless steel
Spring guide: Aluminium, brass, stainless steel, coated steel
Spring: Coated steel, stainless steel, corrosion resistant steel
Seat disc: PTFE

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Gas types: LPG (Propane, Butane)
Connections: Thread
Type: NPT
Pressure range: Max. 27 bar (391 psi)
Capacity: 10,390 SCFM (Air at 120% of set pressure) 
Series available: 3135, A3149, AA3135, W3132G and many others
Sizes and ranges: 1/4" to 2½" 
Standards: UL listed, ASME, CE, PED

*Materials and specifications are subject to generalisation. Our experienced people are ready to help you find the correct fit for your application. 

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  • "Pop-action" = max. protection, min. product loss 
  • Automatic reseating of relief valves after discharging
  • 'Bubble tight' seal
  • Available in configurations that permit direct attachment of vent piping when required
  • Optional pipeaway adapters

Did you know?

If used on manifolds, placement of the clapper disc in an intermediate position could restrict flow through one of the relief valves, causing it to destroy the resilient seat disc

Some relief valves incorporate integral pipeaway adapter with break off groove that protects the valve from piping stress damage

Weep hole deflectors are included in some relief valves to guard against flame impingement on adjacent containers

Get in touch!

Whether you already know what you need, or you would like the opinion of an expert, we are always ready to help you out.