SENTINEL™ Diaphragm Seals and Gauge Guards

Isolate and Protect Process System Instrumentation.

Without proper protection, process fluids regularly contaminate and damage inline instrumentation. SENTINEL Diaphragm Seals, also referred to as gauge guards or gauge isolators, employ a chemically resistant diaphragm to isolate and protect system instrumentation from corrosive process fluids, freezing and slurries.


Isolate and Protect

Protect gauges and other system instrumentation from process fluid contamination and corrosion.

Accurately transfer process pressure without direct contact with process fluids.

Prevent erratic surges and clogging due to solids in process fluids.

Protect gauges from freezing and slurries.

Ensure accuracy and reliability of pressure instrumentation when working with corrosive or solids-laden fluids.

Reduce costs by replacing expensive gauges with low cost utility gauges.


SENTINEL Diaphragm Seals are easily installed, come in a variety of chemically resistant materials, and work in both pressure and vacuum conditions.

CPVC, PVC, Polypropylene, PVDF, 316L Stainless Steel and Alloy 20 housings with EPDM, PTFE or Viton diaphragms.

Pressure ranges up to 1,000 psi (68.9 bar).

Wide variety of gauge options with gauge accuracy of +/- 2% or better full deflection.

Models available with no gauge, custom fills, and factory installed instrumentation provided by customer.

NPT, BSP, socket weld, tri-clamp, flange and union inlet options.

NSF/ANSI 61 available on select models.

seals guarantee

Unconditionally Guaranteed

SENTINEL Diaphragm Seal housings are unconditionally guaranteed for life not to fail or Blacoh will replace them at no cost.


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Build and quote the right model for your application.