Stainless Steel Specialty Valves


Fusible Valves Documents toggle

Fusible Valve - 3 way block and bleedSigma Fusible Valves are available in a wide range of sizes, pressures, temperatures and also include several fusible trigger design methods, stacked ball, pop-top, annulus filled to maximize the use of the low melting alloys for precise activation in case of a heat event that requires complete system shutdown. Depending on the installation and location, there is a fusible valve to meet any requirement and budget.

All stainless steel construction means these units can be mounted in any exposed location including direct-mount to actuator, to assure the device is at the location most likely to experience a fire or increased heat source. Also, with a selection of up to eight separate melting point alloys to choose from, including eutectic and non-eutectic alloys, the user can customize the operational effectiveness by varying the selection in relation to the proximity of the possible heat source. With multiple temperatures available, configurations, port sizes and working pressure designs, Sigma has the widest selection of fusible valves.

The designs available include:

  • 2-way bleed and 3-way block and bleed configurations
  • 1/4" NPT to 1/2" NPT, male and female types
  • 150 psi to 15,000 psi working pressure
  • Melting Temperatures available:
  • Eutectic alloys:158ºF, 203ºF, 255ºF, 281ºF
  • Non-Eutectic alloys: 185ºF, 210ºF, 222ºF, 360ºF
  • Standard Service, H2S Service and Arctic Service
  • 316SS construction

Sigma Fusible Plugs are stainless steel hex plugs in male NPT configuration incorporating the same temperature selections above and are rated to 300 psi working pressure. Port connection sizes are available from 1/4" MNPT to 1-1/2" MNPT. The 1/4" thru 1/2" Fusible Plugs are available pre-mounted in tubing tees to facilitate fusible loop system installation.

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Phone:  972-355-3453
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