消除油井产量定义不同造成试井解释误差方法的研究

STUDY ON HOW TO ELIMINATE ERRORS OF WELL TESTING INTERPRETATION CAUSED BY DIFFERENT DEFINITIONS OF WELL PRODUCTION

计算机技术与计算数学的飞速发展引起了试井解释日趋精细化,现代试井解释中试井工程师使用油井的实际产量井史代替其简化产量井史。试井解释时使用地质部门预先提供的日平均总产液量数据得出的产量井史呈现下降趋势,解释出的资料表皮系数增大,井筒附近呈现伤害特征,与测试井实际状况不符。通过理论计算分析了产量定义不同对试井解释结果的影响,分析了造成测试井产量井史下降的原因。提出了产液速度概念,建立了测试井实际产量修正公式。现场应用表明,试井解释时通过将测试井的日平均产液量修正为产液速度,消除了测试井测压前24 h产量定义不准确造成的解释误差,提高了试井解释精度。

The rapid development of computer technology and computational mathematics has caused the refinement of well testing interpretation. In the modern well testing interpretation,the well test engineer uses the actual production well history instead of simplified production well history. The history of the production wells obtained by using the daily average total liquid production data provided by the geological department shows a downward trend. The skin factor interpreted increases,and the pollution characteristics appear near the wellbore,which is inconsistent with the actual. The theoretical calculations are used to analyze the influence of different production definitions on the results of well test interpretation,and the reasons for the decline in the production well history of the tested wells are analyzed.The concept of fluid production rate is then proposed and the actual production correction formula is established. The field application shows that by correcting the daily average liquid production of the test well to the liquid production speed during the well test interpretation,the interpretation error caused by the inaccurate definition of the output 24 hours before the well pressure measurement is eliminated,and the well test interpretation accuracy is improved.