Research On The Design Of Power Distributional Closed Loop Planetary Gear Reducer For Down Hole Progressive Cavity Pump

The oil production technology utilizing the progressing cavity pump system has the properties of high adaptive, high efficiency, low running fault and running cost, and now has been used more and more widely. But, at the present situation, the down hole progressing cavity pump is driven by the motor and reducer placed on the ground via a thin and long rod, and this cause troubles easily because of the rod works in cycling bending and distortion. So, in order to assure the safety and high efficiency for oil production, it is necessary to place the motor and reducer in down hole to drive the pump directly. This paper focus on the development of a kind of a reducer directly connected to the down hole progressing cavity pump. This development includes the selection of reasonable structure, designing, simulation, manufacturing and testing of the reducer which has the properties of high horsepower to weight ratio and compactness. At first, base on the researching achievements both in home and abroad, the current situation and future development trend of the mechanical oil production technology are presented. By analyzing the different kinds of in use reducer and integrating the current research and considering the down hole operating condition, a kind of closed loop power distributional planetary gear reducer is put forward as a proper reducer to directly connecting the motor and the progressing cavity pump. The feasibility analysis for the proposed reducer is completed, the equations of speed reduce ratio, the bearing torque of each planetary gear, and efficiency of the reducer are developed. Based on the down-hole working condition and the required capability of the reducer, the mathematic module for the reducer optimal design as the function of minimum volume is proposed, the design variable and restrain conditions are determined, and by solving the optimal module, the optimal parameters of the reducer are obtained. By utilizing the optimal parameters, a design case is completed to further verify the speed ratio, efficiency, the power distribution ratio, and thedimension of the reducer. The load distribution method by using the gap of spline which connecting the gear and the shaft in the reducer is put forward. The structure design, 3D modeling, virtual design of the parts, virtual assemble and interference, and the rotating simulation of the reducer are completed by using Solidworks. The finite element analysis for the main parts of reducer is fulfilled and the stress and deformation curves of the main parts in a running cycle are also obtained. Finally, base on the mechanical design manual, the manufacturing techniques, the material, the structure, the heat treatment methods, et al. are determined, and the prototype reducer for down hole use is manufactured, assembled and tested.