Design And Performance Analysis Of Eccentric Wheel Pumping Unit

Due to the high energy consumption of conventional beam pumping unit,it is difficult to achieve low stroke rate.Aiming at this problem,this paper designs a kind of eccentric wheel pumping unit.The main work is carried out in the following four aspects:1.Kinematic analysis.The motion law of the suspension point is established,and the influencing factors of the movement characteristics of the pumping unit are analyzed.Then,the size of the whole machine is optimized with the goal of minimizing the maximum acceleration.It is concluded that the pumping unit moves gently in the upper stroke,which is good for oil recovery.Compared with the conventional pumping unit,the optimized pumping unit has excellent movement characteristics and is more suitable for low stroke oil Wells.2.Dynamic performance analysis.The torque parameters of the reducer were calculated according to the balance and load,and then the dynamic performance was optimized.The suitable working conditions of the single objective and multi-objective optimization scheme were discussed.It is concluded that the net torque fluctuation of the reducer is small after optimization,the CLF value is closer to 1,the energy consumption is low and the dynamic performance is excellent.Single objective optimization is suitable for pumping units with large energy consumption to reduce energy consumption,while multi-objective optimization is suitable for comprehensively considering the performance of various components to improve the dynamic performance of the whole unit.3.Build a virtual prototype,simulate the motion characteristics and dynamic performance according to the actual working conditions,and then study the improvement method of the vibration and impact of pinion and rack.It is concluded that the motion characteristic curve of the theory is the same as that of the simulation,but in the actual working condition,the gear stiffness is large,and the collision of gear teeth causes the acceleration mutation.Friction does not change the acceleration law,and the cutting depth affects the acceleration mutation,and the optimal cutting depth is 0.0006～0.0008 mm.The double circular arc tooth profile can reduce the impact,but the meshing force is large.When the involute tooth profile is modified to reduce the impact,the linear modification method is better.4.Design key components and conduct finite element analysis.It is concluded that the friction has a great influence on the contact strength of the tooth surface.The friction correction coefficient is put forward,which provides a reference for the calculation of the contact strength of the rack and pinion transmission in practice.There is stress concentration at the end of the sleeve.Both broken line and arc modification method can reduce the stress concentration,and the effect of arc modification is better.The eccentric wheel pumping unit has the advantages of excellent performance and low energy consumption,so it has a broad application prospect in low stroke Wells.