海上油气井测试射孔峰值压力预测方法

Peak pressure prediction method for testing and perforating in offshore wells

为有效降低海上油气井射孔测试联作施工安全风险,以东海常用套管、油管、射孔枪、射孔弹组合为参考,建立了射孔管柱有限元数值模型。利用控制变量法,结合射孔峰值压力数值模拟结果,分析了总装药量、井筒初始压力、井筒爆炸空间等参数与射孔峰值压力的相关性,在此基础上,通过多元非线性回归建立了射孔峰值压力的计算公式。利用2口井射孔实测压力结果对公式进行验证,射孔峰值压力相对误差分别为6.1%和9.8%,在合理误差范围内。该公式可用于射孔作业前的峰值压力预测,为现场及时作出安全决策提供指导和支持。

In order to effectively reduce the safety risks in combined perforating and testing process in offshore wells,a finite element numerical model of the perforation string was established based on the commonly used casing,tubing,perforating guns,and perforating charges in the East China Sea.By using the controlled variable method,together with the numerical simulation results of peak perforating pressure,the correlation between three parameters(total charge,initial wellbore pressure,and explosion space)and peak perforating pressure was analyzed.Then,an empirical formula for peak perforating pressure was developed through multivariate nonlinear regression.The formula was validated using measured perforating pressures in two wells,with relative errors of 6.1%and 9.8%,respectively,falling within a reasonable error range.This formula can be employed for predicting peak pressure before perforating operations,providing guidance and support for timely safety decisions on site.