SENTINEL Diaphragm Seals Protect & Isolate System Instrumentation, Guaranteed!

Without proper protection, hazardous and corrosive process fluids regularly contaminate and damage system instrumentation. The strength and durability of Sentinel Diaphragm Seals protect and isolate all forms of system instrumentation for a minimum of three years…guaranteed.*


  • Protect and isolate all forms of system instrumentation from hazardous and corrosive process fluids
  • Ensure gauge and switch accuracy
  • Smooth out erratic pressure surges
  • Extend the life of pressure instrumentation
  • Protect gauges from freezing and slurries
  • Receive accurate and consistent readings when working with corrosive or solids-laden fluids
  • Replace expensive gauges with low cost utility gauges


  • Three year guarantee on diaphragms and seal bodies
  • Accuracy of ±2% full deflection or better
  • Pressure ranges up to 1000 PSI (68.95 BAR)
  • 1/4″ (6.35mm) up to 3/4″ (19.05mm) inlet ports
  • All standard models available from stock
  • Bodies available in a full range of chemically resistant materials
  • Custom models available



Sentinel Diaphragm Seals
Protect & isolate all forms of system instrumentation


Sentinel Diaphragm Seals
Available in a variety of chemically resistant materials


Sentinel “Revolution” Diaphragm Seal
All-PVC construction and threaded housings are ideal for corrosive environments


Sentinel “Flow-Thru” Diaphragm Seal
Prevents “dead-leg” and clogging of viscous process fluids

*Blacoh Fluid Control guarantees its Sentinel Diaphragms and Seal bodies for three years from the date of purchase. If any failure occurs, Blacoh will replace your Diaphragm Seal at no cost to you. Guarantee does not apply to gauges or custom models.

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