Design specifications.

Design and manufacture: GB/T 12235, DIN EN 13709:2003
Face to face: GB/T 12221, DIN EN 558-1
End connection dimensions: HG/T 20592, DIN EN 1092-1
Pressure-temperature: GB/T 9131 ASME B16.34 HG 20592
Test-inspection: GB/T 13927 GB/T 9092 API 598
Helium mass spectrometry leak detection: API 602 MSS SP-117

Application: Suitable for toxic and hazardous media conditions,such as dry chlorine, ammonia, etc.

Design features：
1: Zero leakage seal.
Main seal: Bellows assembly seal, with built-in flush-free design,by hydraulic forming, multi-layer structure, can ensure maximum life extension, expansion and contraction (open/close) up to 10,000 times

at a pressure of 2.5 MPa.
Auxiliary seal: non-metallic packing, using braided packing with corrosion inhibitor, for added reliability, safety and resistance to high temperatures,

providing a maintenance-free condition.
2: Internal limiting device,Increase the upper limit of the valve stem toprotect the safety of the valve in use, effectively protecting the elastic variables

of the bellows and greatly increasing the service life.
3: Sealing surface made of carbide overlay welding, excellent isolation.
4: The bellows is made of special material Hastelloy HC.276.