Optimization And Simulation Of Horizontal Well Hydraulic Tractor

As one of the important technologies of horizontal well development,the mechanical wheel type downhole tractor is widely used.In recent years,hydraulic traction device has emerged to adapt to more complex horizontal well conditions.The wheel hydraulic tractor with hydraulic system as control unit has more traction force,stronger obstacle crossing performance and better control system than mechanical tractor.Therefore,hydraulic tractor has a wider development prospect than mechanical tractor.This paper takes hydraulic tractor as the research object,mainly carries on the following aspects research:(1)The hydraulic tractor system assembly and its functions are studied and analyzed theoretically.It is clear that the most important part of hydraulic tractor is hydraulic traction unit,and the working principle of hydraulic wheel tractor is briefly described.(2)The mechanical model of the traction unit of hydraulic tractor is established and studied.The optimized design method is used to optimize the traction unit.The optimization results determine that when the diameter of the crawler wheel is d=80mm,the size of the driving arm l1=75.70 mm and l3=80.30 mm,the size of the traction unit of the underground tractor can be optimized,and the traction unit has stronger adaptability to the change of pipe diameter after optimization.(3)According to the joint simulation technology,the mathematical model of valve controlled hydraulic motor and cable resistance is interactive with the traction unit model under virtual prototype.The simulation results show that the optimized traction unit can improve the load traction force;under the premise of ensuring the working speed and good control system of hydraulic motor,adjust the amplification coefficient to improve the response speed of the system.The simulation verifies the valve The control hydraulic motor can improve the stability of the hydraulic tractor in operation.(4)Hydraulic system of hydraulic traction device consists of two parts: rotating circuit and hydraulic push system.The model of rotating circuit is established and simulated.It is verified that the hydraulic traction device can still improve the speed when the motor power is low.Through joint simulation analysis,PID control and fuzzy PID control are applied to hydraulic push system.The simulation analysis verifies PID control and model Paste PID control has good control effect on push system.Compared with the fuzzy PID control,the response speed is faster,the simulation curve is more fitted,and the fuzzy PID control is helpful to improve the adaptability of hydraulic tractor when the casing size changes.