同根派生 packing nut相關(guān)詞英漢例句Some wrench-operated valves, specifically those used in ammonia and amines service, have packing nuts with notches machined into the flats.一些扳手型閥門，特別是那些用于氨和胺設(shè)施的扳手型閥門的襯墊螺母帶有加工進平面的凹槽。packing nut更多例句