NK/Z41, NK/Z44, NK/Z941, NK/Z944, NK/Z541, NK/Z544, NK/Z441, NK/Z444, DK/Z41, DK/Z44, DK/Z941, DK/Z944, DK/Z541, DK/Z544, DK/Z441 DK/Z444 [W, H, Y) - PN 10, 16, 25, 40, 64, 100 vacuum isolation gate valves are suitable for use as opening and closing devices on pipelines with working temperatures ≤ 540C and working media such as water, steam, and gas. They are particularly suitable for vacuum condensation and vacuum negative pressure systems of steam turbines in thermal power plants, serving as vacuum isolation seals. 5. They have parallel double seals, semi forced bidirectional seals, small friction during sealing surface movement, easy opening and closing, and self compensation function for sealing surface wear. Valve covers The packing chamber is equipped with a sealing structure, which has a self expanding and compressing effect. High strength materials are used to seal all sides of the joint, making it easy for the system to be completely isolated from the atmosphere and having good system airtightness.