Determination and adjustment method for high-slip motor-driven beam-pumping unit balance

Abstract

The invention relates to a determination and adjustment method for high-slip motor-driven beam-pumping unit balance. The method comprises the steps: a magnetic linkage observation method of a motor is utilized for calculating the rotating speed of a pumping unit motor, dynamic analysis of the pumping unit is combined, and further motion law of a pumping unit crank is obtained; coupling relationship is relieved between a crank motion equation and a wave equation of a sucker rod string, kinematical analysis and dynamical analysis can be carried out on a pumping unit hanging point respectively, the speed, acceleration and displacement of the pumping unit hanging point and load of the hanging point are respectively calculated, torque of the pumping unit crank is calculated, the maximum torques of up stroke and down stroke are compared, and the ratio of the maximum torques is taken as a determination basis for the walking beam balance. The method provided by the invention is high in accuracy and strong in anti-interference performance.

Description

technical field [0001] The invention relates to the technical field of balance adjustment of a beam pumping unit oil production system, in particular to a method for determining and adjusting the balance of a beam pumping unit driven by a high-slip motor. Background technique [0002] The beam pumping unit is the main oil production equipment, accounting for more than 90% of the total oil production equipment. Tens of thousands of beam pumping units have completed 80% of my country's oil production. According to a report of "Research on Energy-saving Technology of Oilfield Surface Production System at Home and Abroad" by the Petroleum Information Research Institute, the efficiency of the pumping well system in the United States is generally 40%, while the efficiency of the pumping system in my country is only 26%. The energy consumption cost of mechanical recovery accounts for a relatively large proportion of the cost of oil production, and the poor balance of the pumping u...

AI Technical Summary

Problems solved by technology

[0008] (2) The rated efficiency of the high-slip motor is lower than that of the ordinary motor, but when driving the pumping unit, it has a higher average efficiency due to the reasonable matching of the machine, rod and pump

However, when the pumping unit is driven by a high-slip motor or an ultra-high-slip motor, the crank speed of the pumping unit can no longer be approximately considered constant, and there are large fluctuations. Assuming that the crank speed is constant, a calculation error occurs

When the crank speed fluctuation factor is taken into account, there is a strong coupling between the established differential equation of motion of the crank and the wave equation of the vibration of the sucker rod string, and it is difficult to solve it

Images