| 摘要 |
A tubular drill pipe having a pin connector at one end and a box connector at the other end has each connector adapted to mate with a connector similar to that at the opposite end of the pipe-but on another pipe, to form a tool joint. The connectors are of the type having two pair of axially abutting make-up faces: a primary annular shoulder formed at the inner end of the base of the pin connector, which mates with the end face of the box connector to form a first such pair; and an internal secondary shoulder at the inner extremity of the base of the box connector which abuts the end of an outermost nose section of the pin connector. The (a) length of the threaded section of the pin, (b) the transverse cross-sectional area of the pin nose, and the smaller of (c) the transverse cross-sectional area of the box counterbore section, and (d) the transverse cross-sectional area of the last engaged thread of the pin are correlated, so that the torsional strength of the joint is approximately equally dependent on each of (a), (b) and the smaller of (c) or (d). |
