Well Trajectory Design And Control Research Of Deep Horizontal Well In Daqing Oilfield

At present, the deep gas reservoir is one of key goals of exploration and development in Daqing oil field. There is rich gas reservoir in deep formation of Xujiaweizi block. But due to the deep depth of conglomerate, strong diagenesis and generally tuffaceous contained, the gas reservoir connectivity is poor. Most of the reservoir is low abundant reservoir which pore degree is less than 6% and the density is more than 2.50g/cm~3. The exposed area of target layer is relatively limited in vertical wells. So the effective development of deep gas reservoirs is a challenge which must be overcame.In recent years, with the development and application of medium radius horizontal wells in Daqing oil Field, horizontal drilling technology in shallow and medium formation is quite mature. But because of the high geothermal gradient, hard formation, high drillability, hard angle build, hard selection of drilling tool, the local flaky formation, and other difficulties in Daqing oil field, horizontal well technology has not been carried out in deep formation. In this paper, in view of the objective factors of long vertical section, difficult control of horizontal displacement in deep horizontal wells, used theoretical analysis and experimental method, the reasonable build-up rate and changing curvature double additional profile method were applied to optimize well drilling trajectory design and drill string design. The drillstring friction and torque model in deep horizontal wells was established. Well trajectory control tools and equipments in deep horizontal wells were selected and configurated. A new horizontal well trajectory design and control technology was formed for Daqing Xujiaweizi deep wells.