Electro-vacuum Differential Pressure Valve DYC-JQ electro-vacuum differential Pressure valve is a safely valve for mechanical vacuum pump.是什么意思_Electro-vacuum Differential Pressure Valve DYC-JQ electro-vacuum differential Pressure valve is a safely valve for mechanical vacuum pump.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句