Hydraulically Operated Safety Valves

Hydraulically Operated Safety Valve has been designed as a rapid action, internal safety valve to facilitate the emergency shut-down of tanks and vessels used for the storage and transportation of LPG, Ammonia, Vinyl Chloride and other hazardous liquids stored at high pressure and usually at ambient temperatures. The valve will “FAIL-SAFE” under all conditions.


The valve is normally held closed by a heavy duty stainless steel spring and hydraulic pressure is applied to hold the valve open. When the hydraulic pressure is released, the valve closes rapidly to ensure safe shut-down in the event of an emergency.

Hydraulic pressure can be released by :

  • Fusible Plugs : Fitted into the hydraulic line and which melt at 740C (1650 F)
  • Frangible Elements : Which can be broken off in an emergency.
  • Quick Manual Release : a feature on the Hydraulic Operator (Figure 7020)
  • Solenoid Operated : suitable for automatic operation when incorporated into a system for remote operation.