drill pipe annulus钻杆: bull rod; bar; rod; drill st ...环: ring; hoop空: leave empty or blank; empty; ...杆环: collar环空: annular; annulus下载手机词典可随时随地查词查翻译关注微信公众号：chachacidian，回复:钻杆环空，即可在微信中查询翻译
