文献类型：专利

英文题名：High efficiency torsion resistant drill stem joint for e.g. petroleum gas extraction, has gap formed between cylindrical holes when inner screw thread piece is matched with outer screw thread piece

作者：GAO L;REN H

机构：[1]UNIV EAST CHINA SCI&TECHNOLOGY

申请号：CN101975032-B

公开日：2012-08-29

语种：英文

收录：DERWENT

摘要：NOVELTY - The joint has an outer screw thread piece including two outer platform shoulder faces, stress reducing groove, long straight cylindrical face, outer screw thread and cylindrical face. One of the platform shoulder faces and long straight cylindrical holes are fixed in a circular arc transition. A connecting circular arc is provided with a 0.8-1.2 mm radius (R1). A gap is formed between the cylindrical holes when the inner screw thread piece is matched with the outer screw thread piece. A stress reducing groove is formed between the straight cylindrical face and the platform shoulder face. USE - High efficiency torsion resistant drill stem joint for a petroleum gas extraction and a natural gas extraction. ADVANTAGE - The joint reduces the stress limit value after the inner and outer screw threads are engaged, and improves the stress limit value and the stress distribution condition of the drill stem joint, and has better connecting intensity and sealing performance and better torsion resistance property. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a high efficiency torsion resistant drill stem joint for a petroleum gas extraction and a natural gas extraction. Length (L1) Connecting circular arc's radius (R1)