Dynamic Simulation And Analysis Of Vertical Planetary Gear Ring Oil Pumping Unit In Emergency Situation

Oil is nonrenewable resources,the earth's oil reserves are less and less,and the world's oil exploitation has entered the middle and late period.The proportion of water in oil is increasing and the dynamic liquid level is dropping in existing wall.In the newly developed oil field,the depth of the oil well pump is also getting deeper and deeper.Therefore,the seriously situation of oil exploitation requires the oil pumping unit develop to the future direction: long stroke,large displacement,and heavy load,high efficiency.The vertical planetary gear ring oil pumping unit adopts the planetary gear ring mechanism to realize the smooth commutation,which has the characteristics of long stroke,large load,low energy consumption and high efficiency.In this paper,the main research contents are as follows:(1)This paper expounds the advantages,disadvantages and scope of application of oil pumping unit with different principles and structures,lists the malpractice of traditional oil pumping unit and proposes the future development trend of pumping unit.This paper introduces the working principle and transmission system of vertical planetary gear ring oil pumping unit.(2)This paper gives an analysis of the calculation model of velocity and acceleration of planetary gear after emergency situation happened at meshing point A and point C,and the Angular velocity and angular acceleration calculation model of the tie rod in ABC segment.This paper also calculate the initial velocity and the acceleration of the gear ring while slider rising meshing at BCDE and EFAB segments.This paper drew the time velocity curve and time displacement curve of the gear ring after the lifting belt cracked at the point A,C,D and F in MATLAB software,which stand for real motion process of the gear ring.(3)On the viewpoint of energy,analysis out that the gravitational potential energy of ring gear is mainly turned to the rotational kinetic energy of planetary gear and tie rod and the strain energy of planetary axis after the emergency situation occurred.This paper completed the system dynamics simulation after the lifting belt cracked at the point A,C,D and F in ABAQUS software,get the maximum strain of the planet shaft in the impacted area,and the maximum stress of the material of the planet's axis dangerous section.The system is simplified to the end of the cantilever beam subjected to impact load,and the maximum stress and maximum strain of the traveling star is calculated theoretically.By comparing the simulation results and theoretical calculation results,the error between simulation results and the theoretical results are small,which can further determine the correctness of the simulation calculation and the theoretical calculation.When defining the planet shaft as an ideal elastic material,the lifting belt cracked at the point A,C,D and F,the impact of the ring gear on the planetary shaft makes the deformation of the planetary shaft less,but the shear stress of the material is very large.After the mesh point is broken at any point of the tooth ring,the material of the dangerous section of the planet shaft is subjected to a large shearing stress.So it is necessary to add a set of safety protection device.When the gear ring speed exceeding a certain value,the safety protection device judges the lifting belt is cracked and forces the speed reduction as soon as possible to avoid the gear ring crash the planet gear.Part of the research results in this paper can provide a theoretical basis for the design and research of safety protection devices.