Our online catalog is being updated! Please contact us for current pricing. Thermionics' Gate Valves Satisfy Stringent National Laboratory Specifications The specifications enumerated below established minimum requirements for high vacuum gate valves for a major national research laboratory. Valves from all foreign and domestic manufacturers were tested for conformance. Thermionics' gate valves were the only domestic valves tested which satisfied stringent specifications of National Laboratory testing. Thermionics was the only domestic valve manufacturer qualified and certified as an acceptable source for valves. A copy of the report is available upon request. Valve Specifications for National Laboratory Testing Stainless steel fabrication consistent with good vacuum practice. All metal sealed with the exception of dry Viton gate seal. Helium leak rates at 1 atm differential: Across valve: < 1 x 10-9 std cc/sec To outside environment: < 1 x 10-10 std cc/sec Must seal with differential in either direction. Hydrocarbon-free interior. All-metal ConFlat-type port flanges. Electro-pneumatic operation with 110 VAC solenoid, uses less than 25 W of electrical power at 80 psi air pressure. Closed valves must remain sealed if air pressure is lost. Valve closes with loss of electrical power. Positive valve position indication available via electrical contacts. Closing and opening time of less than 3.5 sec. Capable of operating 10,000 cycles without maintenance. Valve actuation mechanism removeable with valve body in beamline. Metal bonnet seal must be positively held in position during assembly. Valve cannot emit peak sound levels greater than 85 dB at 2 ft during operation at 80 psi. Valve cannot generate peak vibration levels greater than 15,000 in/sec2 below 2,000 Hz during operation at 80 psi. Valve weight cannot exceed 45 lbs in the 6" I.D. size. Test Procedures The valves were installed into a section of 6" beamline. The valves were cycled 10,000 times, stopping each 1,000 cycles for leak checking in both directions at 1 atm differential. Difficulties in mounting, operation, etc. were looked for. After the cycle test, each unit was dismantled for inspection. Thermionics' gate valves were the only domestic valves tested which satisfied stringent specifications of National Laboratory testing. Thermionics was the only domestic valve manufacturer qualified and certified as an acceptable source for valves.