实体膨胀管性能评价方法研究及应用

Research and Application of Performance Evaluation Methods of Solid Expandable Tubular

为了保障实体膨胀管现场使用安全,建立了一套系统的实体膨胀管性能评价方法,并将该评价方法按内容和使用条件分为3个系列,对每个系列设计了相应的试验项目和试验流程。根据3个系列实体膨胀管性能评价方法,对国内某制造厂生产的L80钢级139.7 mm×7.72 mm膨胀套管进行试验和评价。试验结果表明,膨胀前、后膨胀管金相组织无明显差别;膨胀后套管抗拉强度、硬度显著增大,伸长率和冲击功下降较明显,但满足API 5CT对80钢级的性能要求;静水压69.0 MPa保持30 s无渗漏,爆破压力85.9 MPa,膨胀后挤毁压力28.7 MPa,比膨胀前(66.4 MPa)下降57%,但满足API技术要求。因此,建立的实体膨胀管实物评价方法满足对石油天然气井中大多数实体膨胀管进行性能评估的要求,可保障膨胀管管材的质量和应用安全。

To ensure the application safety of the solid expandable tubular, a set of systematic solid expand- able tubular performance evaluation methods are established and divided into three series based on conditions of use and content. The test items and flows are designed for each series. The domestic L80 steel grade φ139.7 mm x 7.72 mm expandable casing is tested and evaluated according to the three series of solid expandable performance evalua- tion methods. The test results show that the microstructure of solid expandable tubular before and after expansion has little difference. After expansion, the tensile strength and hardness of expandable casing increase significantly. The elongation and impact energy still meet the performance requirements of API 5 CT on the 80 steel grade after an ob- vious decrement during expansion. The solid expandable tubular could withstand the hydrostatic pressure of 69.0 MPa in 30 s without leakage and its burst pressure is 85.9 MPa. After expansion, the collapsing pressure of the sol- id expandable tubular falls 57% from 66. 4 MPa to 28.7 MPa, but still meets the technical requirements of API. The established solid expandable tubular full scale evaluation method meets the majority of oil and gas wells solid expandable tubular performance evaluation requirements, and could guarantee the quality and application safety of the solid expandable tubular.