螺杆式井下增压钻井装置原理及设计

The principle of the screw-type downhole boosting drilling system and its design

为了提高钻探效率,设计了螺杆式井下增压钻井装置,该装置主要由动力单元、动力转换单元、固液分离单元、增压单元以及高压流道单元组成。动力单元将钻井液的水力能量转换为螺杆泵马达转子的转动扭矩,动力转换单元将转子的旋转运动转化为增压缸柱塞的轴向往复运动,固液分离单元对被增压的钻井液进行过滤,增压单元通过柱塞的往复运动来压缩缸内的钻井液,对钻井液增压,高压流道单元将增压后的钻井液输送给钻头的高压喷嘴。现场试验表明,螺杆式井下增压钻井装置除换向机构有较大磨损外,其他零部件均无明显损伤。因此需对换向机构进行改进,以达到螺杆式井下增压钻井装置的寿命要求。

To improve the boring efficiency,the screw-type downhole boosting drilling system was designed.The system mainly consists of power unit,power conversion unit,solid-liquid separation unit,boosting unit and high-pressure flow channel unit.The power unit converted the hydraulic energy of drilling fluid into the rotary torque of the screw pump motor's rotor.The power conversion unit converted the rotation of the rotor into the axial reciprocal motion of the boosting cylinder's plunger.The solid-liquid separation unit filtered the boosted drilling fluid.The boosting unit compressed the drilling fluid of the cylinder through the reciprocal motion of the plunger and pressurized the drilling fluid.The high-pressure flow channel unit transported the boosted drilling fluid to the high-pressure nozzle of the drill bit.The field test shows that all the parts of the screw-type borehole boosting drilling system did not have noticeable damage except for a remarkable abrasion of the reverse mechanism.Therefore,an improvement on the reverse mechanism must be done so as to reach the requirement of the service life of the screw downhole boosting drilling system.