| 摘要 |
A coupling for connecting first and second tubular members, the coupling including a tubular body having a first end portion and a second end portion, a first threaded box formed in the first end portion, a second threaded box formed in the second end portion, the tubular body having an outer, annularly extending surface with at least one groove formed in the outer surface and extending from the first end portion to the second end portion of the tubular body. |
