Standard packing chamber with 125 RMS wall finish, burnished non-rotating stem and PTFE or graphite packing rings. Many times the cycle life of a standard knife gate valve.是什么意思_Standard packing chamber with 125 RMS wall finish, burnished non-rotating stem and PTFE or graphite packing rings. Many times the cycle life of a standard knife gate valve.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句