短語詞組短語vacuum relief cracking pressure 真空安全開啓壓力high cracking pressure 氣動軟琯;擠出級pressure relief cracking pressure 減壓裂化壓力cracking pressure of valve 閥開啓壓力bypass valve cracking pressure drop 旁通閥開啓壓降high pressure hydrogenation cracking 高壓加氫裂化 返回 cracking pressure