论文部分内容阅读
在徐深气田的开发过程中,发现多起气井油管钢穿孔和管柱断裂事故,分析原因主要是由CO2局部腐蚀造成。为准确反映管柱穿孔失效的实际状况,开展了局部腐蚀敏感区间预测研究。通过模拟徐深气田典型井下腐蚀工况,对常用N80油管钢进行了高温高压腐蚀模拟实验,根据腐蚀形貌及局部腐蚀敏感性的分析,探索出环境因素(温度和CO2分压)对CO2局部腐蚀的影响,以及N80钢局部腐蚀的敏感温度-CO2分压组合区间,建立了CO2局部腐蚀敏感区间的预测模型。通过对比徐深气田实际失效油管与模拟实验试样腐蚀形貌,验证了N80钢CO2腐蚀类型和局部腐蚀敏感区间预测的准确性。
During the development of the Xushen gas field, many gas well casing perforations and pipe string ruptures were discovered. The analysis was mainly caused by the local corrosion of CO2. In order to accurately reflect the actual situation of column perforated failure, a prediction of the local corrosion sensitive interval was carried out. By simulating typical downhole corrosion conditions in Xushen gas field, the high temperature and high pressure corrosion experiments of common N80 tubing steel were conducted. Based on the analysis of corrosion morphology and local corrosion sensitivity, the environmental factors (temperature and CO2 partial pressure) Corrosion and N50 steel partial corrosion sensitivity temperature-CO2 partial pressure combination interval, the establishment of a predictive model for the CO2 corrosion partial sensitivity zone. By comparing the corrosive morphology of the actually failed tubing and the simulated test specimen in the Xushen Gas Field, the accuracy of the CO2 corrosion type and the prediction of the local corrosion sensitive interval of the N80 steel was verified.