| 摘要 |
A drill pipe assembly having an elongate tubular pipe section with a first end and a second end, a first threaded tool joint having an outer surface and being attached to the first end of the pipe section, a second threaded tool joint having an outer surface and being attached to the second end of the pipe section, one of the first and second tool joints having at least one radially outwardly facing annular groove formed in the outer surface thereof and a ring of elastomeric material received in the groove, the ring having a radially inner surface and a radially outer surface, the ring preferably having an index signifying a characteristic of the drill pipe. |
