文献类型：专利

英文题名：Drill collar joint, has internal thread piece comprising circular hole, cylindrical hole and circular arc surface in transitional connection with each other, where radius of circular hole is not equal to radius of circular arc surface

作者：GAO L;REN H

机构：[1]UNIV EAST CHINA SCI&TECHNOLOGY

申请号：CN201771439-U

申请日：2010-03-30

公开日：2011-03-23

语种：英文

收录：DERWENT

摘要：NOVELTY - The joint has an internal thread (2) and an external thread (7) that are in interference fit with each other. An external thread piece (1) comprises an end surface conical shoulder, and the internal thread extends from the shoulder along an axis. An internal thread piece (3) comprises a smooth circular hole (4), a cylindrical hole (5) and a circular arc surface (6) in transitional connection with each other from a surface of the shoulder. The circular arc surface is connected with the external thread. Radius (R1) of the circular hole is not equal to radius (R2) of the circular arc surface. USE - Drill collar joint. ADVANTAGE - The joint has better connecting strength and sealing performance. The joint can improve stress extreme value and stress distribution circumstance. DESCRIPTION OF DRAWING(S) - The drawing shows a front view of a drill collar joint. Radius of circular hole (R1) Radius of circular arc surface (R2) External thread piece (1) Internal thread (2) Internal thread piece (3) Smooth circular hole (4) Cylindrical hole (5) Circular arc surface (6) External thread (7)