The Perforating Optimization Design Research Changed Parameters Of Horizontal Well Section

For horizontal wells in the bottom water reservoir, the oil production will rapidly decrease because of bottom water coning, thus controlling or delaying the bottom water coning is of significant importance. Perforating completion is the main completion pattern for horizontal well. If the perforating operates properly, the oil well productivity can reach or even exceed the ideal pollution-free open-hole well productivity, moreover it can also help to delay the bottom water coning in bottom water reservoir. Conversely, it would increase the cost of perforation, induce the bottom water into the wells, and reduce the development benefits of oil wells. Thus for horizontal wells in the bottom water reservoir, we should optimize the perforation parameters, perforation liquid, pressure and technology to acquire the ideal perforating effect. Among these factors, the effect of perforation parameters is more significant. So, the research of perforating parameters’effects on well productivity is crucially important. And we should acquire the quantitative relationship between perforating parameters and productivity, establish theoretical basis for the optimization of perforating parameters, scientific perforating operation, well productivity improving, as well as bottom water coning delay from those studies. Based on the study of percolation mechanism and fluid mechanics theory, a model of variable depth and density perforation for horizontal wells was deduced. Variable depth and variable density perforation is not the same as the previous one, of which the vertical well perforating with uniform depth and uniform density perforating mode is utilized. The calculation results and the analysis of this model indicate that borehole pressure can be adjusted and the inflow section of horizontal well production fluid can be regulated effectively on one hand, on the other hand bottom water coning can be prevented, water free production period can also be increased, and water free recovery can usually be enhanced by optimizing the depth and density distribution. Meanwhile, variable depth and variable density perforation is more effective than vari-density perforation in terms of regulating the inflow section of horizontal well production fluid. On the basis of the above models, we have developed the corresponding engineering software utilizing the Visual Basic6.0, and the field application was carried out. The results imply the correctness and feasibility of our software. This research for horizontal well completion design provides theoretical basis and the optimum design method, which could also give important guidelines for the horizontal well exploitation enhancement.