某井N80-Q油管粘扣及脫扣的分析

Analysis of Causes for Thread Galling and Jump-out of N80-Q Tubings as Used in a Certain Oil Well

摘要: 對Φ73.02 mm×5.51 mm N80-Q外加厚油管發(fā)生的粘扣及脫扣事故進行了現(xiàn)場調查,對粘扣及脫扣樣品進行宏觀分析;對該批油管螺紋接頭加工質量進行了全面檢測;對油管材質進行了理化檢驗;對油管上、卸扣性能和拉伸性能進行了系統(tǒng)試驗。分析認為,油管螺紋加工質量和材質符合標準要求,粘扣是由不符合規(guī)范的操作所引起的,脫扣是由于粘扣后接頭連接強度降低所致。

Abstract: An on-the-site investigation is made into the failures of the thread galling and jump-out of the Φ73.02 mm×5.51 mm N80-Q externally-upset tubings as used in a certain oil well,while visual analysis of the samples taken from the faulty pipes is also conducted. An all-round inspection is made to the processing quality of the thread connections of the said tubings,and relevant physical-chemical tests of the tubings' material are performed,too. Moreover,systematic tests are carried out to the make & break performance and the tensile property of the tubings. Base on the results of the above mentioned analysis and tests,it is identified that the galling fault is caused by maloperation,and the jump-out fault is resulted in by reduction of the connection strength as following the galling,which has nothing to do with the thread processing quality and material of the tubings that are in compliance with applicable standard requirements.