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Exhaust Check Valves (KF Flanged)

These simple check valves help prevent air in rush into a system after powering down the rough pump. Typically installed on the exhaust side of the roughing pump they can prevent oil back streaming upon pump shut down or failure. Uses either a gravity sealed elastomer ball for traditional vertical installations or a spring-loaded O-ring sealed disc for installation in any orientation.


  • 316 Stainless Steel body with FKM Seals
  • Minimum relief pressure of 7mbar
  • Leak rate: 1x10-5 mbar-L/sec
  • Recommended in operating conditions where air in rush could pull particulates back into the system
  • Reduces oil back streaming from wet pumps
  • Temperature Range: -5°C to 100°C (approx.)

Specifications Table

Manufacturer KJLC
Pressure Torr
7.500 x 10-5 Torr
1.000 x 10-4 mbar
Rates Leak Rate
1.000 x 10-5 mbar*L/s
7.520 x 10-6 Torr*L/s
Minimum Relief Pressure
7.00 mbar
5.25 Torr
Temperature Bakeable
100 ºC
212 ºF

Valve Body
316L SS
Valve Seal
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Flange Selection Guide
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