Overview: J641H pneumatic double acting cylinder shut-off valves, or use the chamber inlet to the lower chamber intake valve remote control, easy to operate and flexible. Cylinder use of media: air, nitrogen. Simple structure, easy maintenance and manufacturing; small working stroke, opening and closing time is short; closing body (valve) and seat sealing surface with cone seal, small closing force, resistance to erosion, reliable sealing. Replaceable seat for the seat, can be any combination of closed counterpart sealing surface material to meet the conditions required to extend the service life. Features: 1, selected materials, in line with domestic and foreign standards, reasonable structure, beautiful shape. 2, the valve seat sealing surface using iron-based alloy or Stellite (Stellite) cobalt-based alloy cladding, wear resistance, high temperature resistance, corrosion resistance, anti-abrasion performance, long life . 4, stem quenched and surface nitriding treatment, good corrosion resistance and scratch resistance. 5, can be a variety of standard pipe flanges and flange sealing surface types to meet various project needs and user requirements. 6, the full range of body materials, packing, gaskets, according to the actual working conditions or user requirements reasonable matching can be applied to all kinds of pressure, temperature and medium conditions. 7, inverted sealed with screw connection seal seat or body made of austenitic stainless steel welding, reliable seal, replace the packing can be carried out without stopping the machine, convenient, does not affect system operation.