Vacuum valve 
 First, the purpose and characteristics of the vacuum valve 
 The form of sub-vacuum valve flange connection, welding the two, drive a manual, electric two. The valves for working temperature ≤ 425 ℃ and ≤ 550 ℃, the working medium is water, steam or air in the pipes on the road, as the opening and closing devices; especially for power plant steam condensation and vacuum system, isolated from the vacuum seal effect. 
 1, the design of the vacuum seal structure packing room, the system is isolated from the atmosphere, with good environmental performance. 
 2, selected materials, break all international standards, the overall high quality materials. 
 3, sealing pair advanced and reasonable, to improve the sealing performance and long life. 
 4, the opening and closing parts are parallel to the gate-way flexible seal, friction is small, open and close easily, easy maintenance, reliable sealing, excellent performance. 
 5, stem quenched and the nitrogen treatment, with good corrosion resistance, resistance to abrasion and wear resistance. 
 6, flange gaskets made of composite materials, expansion coefficient, airtight performance, ensure system reliability and atmospheric isolation. 


 Vacuum valve vacuum valve 

 Second, the scope of application of vacuum valve 
 Design and manufacture of GB/T12224 JB/T3595 
 Connector size length of the structure GB/T12221 
 Flange size JB/T79 
 Inspection and test JB/T9092 
 Material carbon steel GB/T12229 
 Stainless steel GB/T12230 
 Steel Q/ZB66 
 Logo GB/T12220 
 Availability JB/T7928 

 Third, the vacuum valve materials and use of the main components 
 Valve cover gasket valve stem packing for the valve plate for medium temperature (≤ ℃) 
 WCB WCB + D507MO Stellite6 2Crl3 flexible graphite water, steam 425 
 ZGlCr5MO ZGlCr5M0 + Stellite12 Stellite6 4Cr9SI2 flexible graphite water, oil, steam 540 
 ZGlCrl8Ni9Ti ZGlCr5M0 + Stellite12 Stellite6 1Crl8Ni9Ti PTFE water, steam, corrosive steam 200