Research On Optimized Drilling Technologies For Xing4 Block In Daqing Oilfield

There are many faults and thin-poor layers developed in Xing 4 block, and the drilling engineering has a big venture for its complex geology and geological structures, so how to cut down the cost of drilling and improve the economic performance is the economic target which the drilling engineering and technique pursued all the time. It is important to optimize the parameters of drilling engineering. In this paper, the geological and structural characteristics, and drilling uncertainty and complexity of Xing 4 block(especially the geological structures, causes of formation of borehole collapse, loss of well and borehole shrink and their effects on drilling and preventive measures) are investigated. An optimum design proposal has been selected in this research through the laboratory and field experiments of drilling fluid, make-up of string and completion technique. It can reduce the drilling cycle and cut down the cost of drilling and has a good sense to the oil layer protecting works. The component capabilities of drilling fluid have been analyzed. According to the conditions of oil layers in this area, the reasonable compounding formula has been confirmed through the test of drilling fluid system. Through the study of flowage principle of drilling fluid, different size aiguilles should be used according to the variable well depth. So it can farthest exert the energy of water power to increase the drilling speed and reduce the downhole accidents. Through analyses the cause of borehole inclination, the amount of antifluctuator and the setting position have been summarized. The influence of drilling parameter to borehole inclination and the reasonable make-up of string were summed up. The reasonable density of drilling fluid has been conformed according to the experience method of oil layer protecting. And the reasonable density of well cementation fluid has been conformed according to the pressure that calculated by electrical logging curves, it can provide feasible cementing method and completion technique to protect the oil layers. The field testing in Xing4 block indicates that the optimized drilling technologies are feasible and commercial.