Productivity Prediction Of Radial-branch Horizontal Well

The radial-branch horizontal well is a very important drilling and completion new technology which is adapting the current need of the development of oil field. At the same time, productivity prediction is also one of important base of development engineering in oil & gas field. This paper compares and analyses the applicability and precision of kinds of prediction models based on the investigation of domestic and abroad literature; revises the model from the aspects of considering the borehole friction loss and completion method; builds well length and borehole optimization model which takes the economics factor into account in the condition of steady state flow and get the solution of the model as well; put forward the confirmation method about the azimuth of horizontal part; make study on the decline rule of rates; finally design and develop the productivity prediction software of radial-branch horizontal well, applied for W-5 well of JiangSu oil field, the accuracy of forecast is well. Electrical analogy experiment is applied to study the isobar characteristics of radial-branch horizontal well, and useful conclusion has been drawn. First, the isobar shape is closely correlated to the inclination between the number of well bore and horizontal section length. Second, the production ratio calculated from the revised formula is basically consistent with electricity ratio. Paper also studies the factors affecting the performance of radial-branch horizontal well, including the number of well bore, horizontal section length, position of well, reservoir thickness, aeolotropism. The results reveal that the revised model is fit for actual production. The advisable horizontal section length is available, the 3 or 4 well bore is reasonable.