论文部分内容阅读
目前定向射孔压裂时起裂压力的预测仅立足于裸眼的情况,忽视套管对起裂压力的影响,在工程应用中将产生较大的误差。考虑套管作用,推导建立定向井井周应力模型。假设地层岩石为张性破坏,并综合以上模型,得到定向射孔井水力压裂起裂压力和起裂角的预测模型。根据该模型编程开发一套定向射孔压裂起裂与射孔优化的软件,可预测定向射孔井的压裂起裂压力和起裂角,并优化选择射孔角度和射孔长度。应用软件对渤海油田三口井进行模拟计算和射孔优化,结果发现,模型的起裂压力预测结果与现场实测结果误差最大仅为4.33%,预测的起裂角也与实际结果相一致,从而验证了本模型的正确性。模型和软件对于现场压裂施工和射孔优化有重要的指导作用。
At present, the prediction of initiation fracture pressure in directional perforation fracturing is based on the naked eye only, ignoring the influence of the casing on the cracking pressure, and will have a large error in engineering application. Considering the casing effect, we derive the model of directional well circumferential stress. Assuming that the stratigraphic rocks are zonal damage, and combining the above models, a prediction model of hydraulic fracturing initiation pressure and cracking angle in directional perforating wells is obtained. According to the model, a set of software of directional perforation initiation and perforation optimization was developed to predict the fracturing initiation pressure and initiation angle of directional perforation well, and to optimize the selection of perforation angle and perforation length. Three wells in Bohai Oilfield are simulated and perforation optimized by application software. The results show that the maximum error between the predicted pressure and the field measured results is only 4.33%, and the predicted cracking angle is also consistent with the actual result, so as to verify The correctness of this model. The model and software have an important guiding role in the field of fracturing construction and perforation optimization.