Driving System Of Downhole Driving Reciprocating Pump

The rodless production is also one of the current artificial lifting methods.Aiming at the problems of complex transmission links,low efficiency and eccentric wear of rod and tube in rod production wells,and in order to adapt to special wells such as directional wells and large inclined wells,a new type of sucker rod-less pump lifting scheme is proposed and designed,in which the gear rack is used as transmission mechanism to realize the conversion of planar rotary motion to vertical planar reciprocating motion.The reciprocating pumps are driven by rotary motors for manual lifting.By comparing the advantages and disadvantages of two different schemes of downhole driving reciprocating pumps,the paper chooses ball screw and gear rack as transmission mechanism respectively,and finally chooses gear rack as transmission mechanism,designs the main parts of downhole driving reciprocating pumps transmission system,and carries out modal analysis of the bevel gear mechanism at the output end of the system.The results show that the minimum natural frequency is much larger than the excitation frequency of the system,and there will be no resonance phenomenon.At the same time,the three-dimensional model is established,and then the transmission system model is simplified.In order to facilitate the analysis,the model is concentrated on the gear rack,and its dynamic simulation is carried out.The output response of the gear rack is mainly analyzed,and the variable acceleration start-up is obtained.At the same time,the vibration impact caused by the inertia of the system can be reduced to a certain extent.Finally,the optimal design of the rack and pinion in the transmission system of the downhole driving reciprocating pumps is carried out,and its optimization mathematical model is determined.Taking the minimum volume as the objective function,the modulus,the number of teeth and the width of teeth as the design variables,the design variables are constrained.Finally,the fmincon in the MATLAB software is used.Function is used to optimize the transmission system.The results show that the volume of the system decreases,the reliability increases,and the coincidence degree is almost unchanged before and after optimization.