Research On A New Ball Screw Linear Drive Pumping Unit

At present,the beam pumping unit is the main type in the mechanical oil production system of oilfield.The conventional beam pumping unit has some problems,such as long transmission chain,low system efficiency,high energy consumption and difficult installation and transportation.With the development of motor technology and ball screw technology,a new type of ball screw linear drive pumping unit is proposed in this paper,in order to develop a kind of energy saving wellhead direct drive pumping unit on the basis of reducing the transmission chain of the pumping unit.The new ball screw linear drive pumping unit adopts the motor to drive the ball screw pair directly,and the rotating motion of the motor rotor is directly converted into the up-down reciprocating translation of the lead screw,so as to drive the rod of the pumping unit to do up-down reciprocating motion.Based on the initial prototype developed and combined with the research results of theoretical analysis and laboratory tests,this paper proposes improvement measures and carries out theoretical analysis.Specific research contents are as follows:1.Based on the classical theory of suspension point dynamics of conventional pumping units and combined with the dynamic characteristics of the suspension points of linear driven pumping units with ball screw,the suspension point kinematics and load of linear driven pumping units were analyzed,and the suspension point dynamic characteristics of the units studied in this paper were compared and analyzed;2.The initial prototype was tested on the indoor test platform of the linear drive pumping unit with ball screw,and the working characteristics of the pumping unit under different strokes and strokes were obtained;The initial prototype simulation model of the pumping unit is established in the AMEsim simulation analysis environment,and the suspended point load characteristics and motor operating characteristics of the pumping unit under different well conditions are obtained and analyzed through the simulation analysis,which provides a theoretical basis for the improvement of the initial prototype;3.A new gas-liquid two-phase non-dynamic balance system driven by ball screw linear pumping unit is established in the AMEsim simulation analysis environment,and the simulation analysis is carried out.The theoretical research results show that the energy saving rate of the improved pumping unit is up to 60%;4.Aiming at the slender structure of the proposed new ball screw linear drive pumping unit,simulation research on wind load resistance of the body of the pumping unit was carried out in Ansys environment.The simulation results show that the designed pumping unit has good wind load resistance.The new ball screw linear drive pumping unit has short transmission chain and light mechanical weight.Compared with the traditional beam pumping unit,the new ball screw linear drive pumping unit has the advantages of convenient installation and transportation and high energy efficiency.Combined with the experimental and theoretical research results of this paper,the proposed pumping unit provides a new type of energy-saving pumping unit for oil field exploitation,especially for the exploitation of low production Wells.