Standard Products - Vacuum Seal-Off Valves

PHPK combination vacuum evacuation and over-pressure relief valves are manufactured using only 300-series stainless steel material. All valves are designed to relieve at approximately 15 psig.

Vacuum seal-off valves, part of a complete line of PHPK cryogenic hardware, have been designed to fulfill every system designer’s requirements for a safe, reliable method of vacuum closure.

Each PHPK seal-off valve is all-stainless steel construction, equipped with a double fluorocarbon rubber (Viton) O-ring seal (to prevent vacuum loss from vibration or shock) and threaded-cap, spring-loaded, Viton O-ring sealed relief to prevent moisture and contamination from entering the valve internals. All threaded parts are plated with a patented plating process to PHPK specifications to prevent galling and corrosion. The seal-off valve assembly provides a combination vacuum pump-out opening, seal-off, and relief device. Available in a number of configurations, including plain or with a 1/8” FNPT threaded port for vacuum thermocouple gauge tube connection.