试井设备介绍英文课件PPT introduction_of_well_testing_technique.pptVIP

　　表皮系数S是表皮效应（或趋肤效应）的定量性质。它是由地层不同程度的堵塞、地层钻开程度及钻开性质不完善等因素造成。它的存在将产生一个附加压力降△Ps=0.87mS。 　　堵塞比DR是实测生产压差与理论生产压差的比值（Pi-Pwf）/（Pi-Pwf- △Ps ）。DR数值越大表明堵塞程度越严重，DR值小于1则表明存在负表皮效应（如井眼扩大或井眼附近存在裂缝等）。 　　通过测试资料解释处理还可以计算出地层流动系数（Kh/μ）、产能系数（Kh）、流动效率（FE）、采油指数(Jo)、地层导压系数（η）。除地层参数外，钻杆测试还可以获得地层流体特性参数。 Jo (采油指数)=Q/△P, the productivity index, the value of ratio of actual productivity to actual producing pressure drop. FE (流动效率)=(Pi-Pwf- △Ps)/(Pi-Pwf), the flow efficiency, the value that results when the actual productivity index is divided by the productivity index predicted from Darcys law. Flow efficiency is greater than 1 in a stimulated well (skin 0) and less than 1 for a damaged well. Pi (原始地层压力), initial formation pressure, it is measured in initial shut-in period or extrapolated from Horner curve. d (边界距离), the distance from reservoir boundary. Pressure records interpretation Technique of Formation Test --DST To test the possible hydrocarbon zones in time during drilling operations Least influence on test result which caused by formation damage, the test result can reflect actual conditions of testing zones Least effect on pressure record which resulted in by wellbore storage Shorter testing duration Advantages of DST WFT is a process to use wireline to convey pressure gauge and sample chamber into the well, measure formation pressure and collect formation fluids samples in place, make evaluation for formations properties, and provide the basis for making optimum well completion modes and development plan. It is the most direct method of well logging for determining formation permeability. Comparing with DST, it is more convenient, quick, and cost-effective. Technique of Formation Test --WFT Technique of Formation Test --WFT The first WFT tools was introduced by Schlumberger in the 1955, it has only one function of collect formation fluids sample; WFT tools with functions of pressure record and collect fluids sample; RFT (repeated formation tester, Schlumberger, 1975) FMT (for