射孔参数对热采井套管抗热应力能力影响分析

热力采油使得套管承受较高水平的热应力,增加套管损坏风险,从而降低套管使用寿命。针对射孔参数对热采井射孔套管抗热应力能力的影响规律研究较少。利用有限元软件建立三维套管模型,结合基于应变的设计方法评价热采井射孔套管的抗热应力能力。结果表明,在安全内外压作用下,射孔排包含射孔数目较多且射孔直径较小的射孔参数可增强射孔套管的抗热应力能力;多轮次蒸汽吞吐过程对套管受热变形具有累加效应,保证强度安全前提下选择使得射孔排包含射孔数目较多的射孔参数组合可使得套管满足热应力安全性。研究结果从射孔参数对套管抗热应力能力的影响角度出发,为热采井实际射孔参数方案优选提供了参考。

Analysis on the effect of perforating parameters on thermal stress resistance of thermal production casing

Thermal production exposes casing to high thermal stress, increasing the risk of casing damage and thus reducing casing life. Few studies focus on the impact of perforation parameters on thermal stress resistance analysis for perforating casing in thermal production well. In this paper, finite element software is used to establish 3D casing model, the strain-based design method is used to evaluate the thermal stress resistance of perforating casing in thermal production wells. Under the action of safe internal and external pressure, the thermal stress resistance of the perforating casing can be enhanced by the perforating row containing more perforating holes with smaller diameter. The process of steam huff and puff has an accumulative effect on casing deformation, the thermal stress resistance of casing can be satisfied in the process of multiple rounds of production by selecting proper perforating parameters, under the premise of ensuring the safety of strength, the combination of perforating parameters that make the perforating row contain more perforations can optimize the safety of thermal stress. Based on the influence of perforation parameters on casing thermal stress resistance, the results provide a reference for the optimization of practical perforating parameters for thermal production wells.