某井N80钢级套管脱扣和粘扣原因分析  

Analysis of Causes for Thread Jump-out and Galling of N80 Casings as Used in One Oil Well

作　　者：吕拴录[1,2] 袁鹏斌[3] 张伟文[2] 韩勇[4] 付道明[2] 沈建新[2] 龚建文[2] 樊文生[2] 

机构地区：[1]中国石油大学机电工程学院,北京100249 [2]中国石油塔里木油田公司,新疆库尔勒841000 [3]上海海隆石油管材研究所,上海200949 [4]西安摩尔石油工程实验室,陕西西安710065

出　　处：《钢管》2010年第5期57-61,共5页Steel Pipe

摘　　要：对某井Φ139.7mm×7.72mm N80钢级长圆螺纹套管脱扣和粘扣事故进行了详细的调查研究。分析认为套管发生脱扣的原因主要是由于下套管上扣时螺纹接头发生严重粘扣,使其连接强度大幅度降低所致。该井井口中心与管柱轴线偏离较多,且采用钻杆液压钳下套管,在上扣过程中套管接箍严重夹持变形,外螺纹接头与严重夹持变形的接箍上扣配合之后导致套管严重粘扣损坏。套管严重粘扣还与套管本身抗粘扣性能差有一定关系。In-deep investigation and studies are made into the failures of long round thread jump-out and galling of the Φ139.7 mm×7.72 mm N80 casing as used in one oil well.It is identified through the analysis that the main cause for the said casing thread jump-out is the serious galling of the thread connection as occurred in the make-up process of the casing,during casing running operation,which leads to the connection strength is tremendously reduced.The wellhead center offsets the casing string axis too much,and the coupling is seriously deformed during the make-up process due to clamping with the hydraulic drill pipe jaws.As a result,the matching between the pin and box gravely deformed coupling causes the galling damage of the casing connection.Moreover,the galling of connection is also related to the poor galling-resistance of the casing itself.

关 键 词：套管 脱扣 粘扣 连接强度 上扣操作 

分 类 号：TE931.2[石油与天然气工程—石油机械设备] TE28