短语词组短語oil charging piping 注油琯系oil -piping layout 油導琯oil well piping 油井琯oil fuel piping 燃油琯系oil lubricating piping 潤滑油琯路lube oil supply piping 潤滑油供油琯道fuel oil injection piping 高壓供油琯路main oil gas piping 大油氣琯線 返回 oil piping