短語詞組短語bumper r sub 震擊器Lubricated fishing bumper sub 閉式下?lián)羝?/li>long strke bumper sub 長沖程震擊器sealed bumper sub 油封式震擊器fishing bumper sub 打撈伸縮節(jié);打撈緩沖器drill string bumper sub 鑽柱減震器surface bumper sub 地麪震擊器oil -sealed bumper sub 油封式震擊器pressure balanced drilling bumper sub 壓力平衡式鑽井震擊器 返回 bumper sub