Research On Optimization Design Of Single String Double-acting Pumping Well

Sandstone reservoir occupies a large proportion of oil field in China, but the sands reservoir generally have basic geological characteristics of heterogeneous, multi-reservoir, etc., with the oil exploration gradually into the middle and late phase, the effects of heterogeneity of the reservoir become more and more serious to yield.As a new kind of pump, double-acting pump can adapt to oil production by layer, which is characterized by avoiding effects of the upper and lower reservoir heterogeneity, inter-layer interference pressure differences, as well as the physical properties of reservoir fluids. In this paper, using the numerical reservoir simulation method to simulate two heterogeneous reservoirs, getting the conclusions that using stratification pump exploit separately has more superiority than ordinary mining exploration, also giving use boundaries of stratification pump technical. Results show that the reservoir pressure coefficient of up and down layers is greater than 1.8 or reservoir permeability range is greater than 10, the commingling production is lower than 70% of mining production, at this point, it is suit to use double-acting pump to exploitate to avoid production losses caused by the interference between the layers.Take type of mixing stratification pumps, separate body hanging out mixing stratification pumps, points by separate pump as the study objects, describes their work principle and calculation methods of theoretical displacement, analyzes string force as well as its plunger force, establish the corresponding string and rod string force model, combine with the well lift optimization model, using Visual Basic6.0 prepared a “optimization design of single string stratification pumping well” software. Take well DB1-1-8 for example, Based on the field gathering basic data of oil wells, fluid physical parameters and production data, analyzing the working condition of stratification pump wells, checking the working condition, analyzing pipe stress, and the fixed rod string design, pump diameter combination optimization, dynamic optimization design are done, and alse analyzing the related factors on the result of optimization. Compared with the fixed rod string optimal design results, the difference of the results of the rod string optimal design is not so big, but the optimal system efficiency is bigger.According to the well DB1-1-8 optimization step, the other 14 stratification pump wells in this area are also optimized, so as to provide a reference basis for the subsequent optimizing production.