对某井在稠油开采、反注稀油过程中发生的油管挤毁和断裂事故进行了调查研究。对挤毁油管和同批新油管取样进行材质分析、尺寸测量和挤毁试验,认为油管材质和尺寸均符合标准要求。对挤毁油管外表面形状检查结果表明,油管挤毁之前没有机械损伤,油管挤毁与机械损伤无关。通过推理分析,认为油管首先发生挤毁,然后才发生断裂。通过力学分析和计算,认为油管挤毁和断裂的原因是其所受的外力超过了油管的屈服强度。

Investigation on an accident of tubing collapse and fracture happening during injecting diluted oilinto casing for exploitation in one dense oil well was done.It was considered that the tubing was in accordance withthe standard requirement based on material inspection,dimension measure and tubing collapse test.It was found outthat the tubing collapse was not related to mechanical damage because there was no mechanical damage on the tubingsurface before collapse by inspecting the collapsed tubing.It was concluded that the tubing was collapsed first,andthen fractured by reasoning and analysis.It was found that the cause of the tubing collapse and fracture was the loadborne on tubing exceeding its yield strength according to mechanics analysis and calculation.