Use Wto express seat facing ring material which process directly by valve body,when seat and discsealing material are different,use low hardness material symbol to express (except diaphragm valve).
Use Wto express seat facing ring material which process directly by valve body,when seat and discsealing material are different,use low hardness material symbol to express (except diaphragm valve).
注：由阀体直接加工阀座密封面材料用W表示，当阀座和阀瓣（闸板）密封材料不同时，用低硬试验材料代号（除隔膜阀外）。