定向井压裂射孔方位优化

摘要

In order to solve the problems of high fracture pressure and possible fracture diversion in directional well fracturing,a calculation model for three-dimensional stress field around any directional well trajectory has been set up based on the coordinate transformation method. On this basis, taking into consideration in-situ stress,pore pressure, wellbore fluid pressure, wellbore conditions (inclination, azimuth) and other physical and mechanical properties,etc,a perforation orientation optimization method for directional well was put forward,and analysis of optimum perforation orientation at different deviation angle and azimuth performed. Field application shows that optimized perforation orientation could significantly reduce fracture pressure and improve the effect of fracturing.%为了解决定向井压裂过程中存在的破裂压力高及易发生裂缝转向等问题,基于坐标变换,建立了定向井的井周三维应力场计算模型.在此基础上,综合考虑原地应力、孔隙压力、井筒液柱压力、井眼条件(井斜角、方位角)及其他物理力学性质等因素,建立了定向井射孔方位优化设计方法,分析了不同井斜角、方位角组合下的最佳射孔方位.现场应用表明,利用定向井射孔方位优化设计方法对射孔方位进行优化,能有效降低破裂压力,提高压裂改造效果.