Abstract:
Conventional completion techniques involving inflow-control screen in horizontal wells are characterized by short packing intervals,limited packing intervals,difficulties in the installation of packers in deep wells and other technical challenges.Under such circumstances,research has been conducted to develop completion techniques involving gravel-packing inflow-control screens in horizontal wells.Based on studies related to technical principles and technical challenges in completion techniques involving gravel-packing inflow-control screens in horizontal wells,the advantages and drawbacks of screens of various types were reviewed.Subsequently,screens with choke nozzles or those with flowing channels were deployed.In consideration of requirements for completion involving grave-packing inflow-control screens in horizontal wells,polymer gravels with lower densities were used as packing gravels.Tests were conducted to assess the packing performances of gravels.Relevant results showed the gravel-packing layers could effectively eliminate horizontal flow of fluids in the borehole.Consequently,the layers might serve as packers.By highlighting gravel-packing techniques,completion techniques involving gravel-packing inflow-control screens in horizontal wells were developed.Field applications were performed in the horizontal Well A in the Tahe Oilfield.Compared with those before application,the the well productivity was enhanced by 411.8%,where as the water-cut was reduced by 13.5percent.Research results showed the completion techniques involving gravel-packing inflow-control screens in horizontal wells could effectively enhance the accuracy of the screen to stabilize oil production and to minimize the water cut. Such innovative technologies may be deployed more extensively to enhance production performances.