The material of pneumatic pneumatic valve have?

pneumatic pneumatic valve, just as its name implies is with the aid of a pneumatic valve of the aerodynamic force, usually with the aid of compressed air driven. Below, we come to know about the material pneumatic pneumatic valve in detail what are?
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pneumatic valve body material should give priority to with nodular cast iron, and indicate the brand and the physical and chemical testing data of cast iron practice.
, pneumatic valve stem material
to stainless steel pneumatic valve stem ( CR, large diameter pneumatic valves should also be embedded package of stainless steel stem. Material

and nuts with cast aluminum bronze, brass or aluminum and hardness and strength is greater than the pneumatic valve stem.
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the pneumatic valve stem bushing material hardness and strength shall be no greater than the pneumatic valve stem, and soaking in the water condition and pneumatic, pneumatic valve stem don't form the electrochemical corrosion.
and materials of sealing surface differ
a pneumatic valve, pneumatic have different categories, different sealing methods and material requirements;
b, general pneumatic wedge gate valve, the material of copper ring, fixed way and grinding way shall specify;
c, pneumatic soft sealing gate valve, pneumatic valve plate rubber lining material physical chemistry and health testing data;
d pneumatic valve, pneumatic butterfly valve should be easily identified on the sealing surface material and the butterfly plate on sealing surface material; Their physical and chemical testing data, especially the health requirements of rubber, ageing resistance, wear resistance; Usually use NBR and epdm and so on, are strictly forbidden to mixed with reclaimed rubber.
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a pneumatic valve shaft filler, due to the pipe network in pneumatic pneumatic valve, usually open/close not frequent, packing in a few years no activity, the packing is not aging, long sealing effect;
b, pneumatic valve shaft packing should also be under frequent opening and closing, good seal effect;
c, in view of the above requirements, pneumatic valve shaft packing to lifetime don't change or more than ten years will not be changed;
d, packing if need to change, should consider to have hydraulic pneumatic pneumatic valve design conditions change.