Contact UsFakai Valve Factory Site: Yongxing Industrial Zone, Longwan District, Wenzhou City Tel: 0577-88767789
Contact: Mr. Wang Email: firstname.lastname@example.org
Material of pneumatic check valveRelease Date: July 23, 2019
Material of pneumatic check valve
1. The material of the valve body should be nodular cast iron, and indicate the grade and actual physical and chemical test data of the cast iron.
2. The material of the valve stem, strive for the stainless steel valve stem (2CR13), and the large-caliber valve should also be a stainless steel embedded valve stem.
3. The nut material is cast aluminum brass or cast aluminum bronze, and the hardness and strength are greater than the valve stem.
4. The material of the valve stem bushing should be no greater than the hardness and strength of the valve stem, and it should not form electrochemical corrosion with the valve stem and the valve body under water immersion.
5. Material of sealing surface:
① Different types of pneumatic valves, different sealing methods and material requirements;
② For ordinary wedge gate valve , the material, fixing method and grinding method of copper ring should be explained;
③Physical, chemical and hygienic test data of soft-sealed gate valves and valve lining rubber materials;
④The butterfly valve should indicate the material of the sealing surface on the valve body and the material of the sealing surface on the butterfly plate; their physical and chemical test data, especially the hygienic requirements of rubber, anti-aging performance and abrasion resistance performance; it is strictly forbidden to mix recycled rubber.
6. Valve shaft packing:
① As the pneumatic valve in the pipe network is usually opened and closed infrequently, the packing is required to be inactive for several years, the packing is not aging, and the sealing effect is maintained for a long time;
② The valve shaft packing should also have good sealing effect when subjected to frequent opening and closing;
③ In view of the above requirements, the valve shaft packing is not to be replaced for life or to be replaced for more than ten years;
④ If the packing needs to be replaced, the design of the pneumatic valve should consider the measures to be replaced under the condition of water pressure.