Internal pressure relief valves for LPG/NH3 equipment protection

Internal relief valves are commonly used to protect equipment like mobile tanks and containers. They prevent over-pressure accidents and are specifically designed for ASME tanks and containers while others suit bobtail and transport trucks and construction equipment.   

Product description

These valves come in fully or semi-internal types to conform to different installation requirements. Unlike the standard full-range gradual relief, these internal pressure relief valves feature a 'pop-action' functionality that ensures a full discharge once pressure exceeds a predetermined limit.

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Body: Stainless steel, brass
Spring: Stainless steel, steel, coated steel
Stem: Stainless steel
Seat disc: Resilient rubber, resilient synthetic rubber or Viton
Stem bushing: 17 to 4PH stainless steel

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Gas types: LPG (Propane, Butane), NH3 (Ammonia, Anhydrous Ammonia)
Connections: Thread
Types: NPT
Pressure range: Max. 27 bar (391 psi)
Capacity: Max. 453 m3/h
Sizes and range: 3/4" to 3"
Standards: UL listed, ASME

*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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  • Low profile design (no shearing or distortion)
  • Tamper-proof functioning parts
  • Longer spring size to minimise stress cracking in service
  • Easy installation and removal
  • High capacity - low turbulence
  • Dependable shut-off after opening
  • Built-in spring stop
  • 'Pop-action' minimising product loss
  • Automatic re-seating after pressure equalisation

Did you know?

Internal valves are suitable for many different applications

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