Design And Research Of Hydraulic Control System Of Seal Ring Test Bench

In order to simulate the working condition of the main drive seal of the shield machine in the mixed environment of water,sediment and various oils and grease,and to solve the problem that the existing experimental device cannot make the sealing ring work in the left and right cavities with different pressure points and different working media,the paper designed and studied the sealing ring test bench.The seal ring test bench can adjust the spindle output speed and torque,and conduct different type matching according to the need to simulate the working environment of the shield machine's main drive seal,and conduct friction and wear experiments on the seal ring.Aiming at the control problem of pressure precision,the paper adopts the method of combination of pressure closed-loop control and electro-hydraulic proportional technology to design and study the control system of sealing ring test bench.According to the function and technical requirements of the test bench,make clear the technical scheme and working principle of the hydraulic system of the sealing ring test bench,and select the actuator of the hydraulic system.The mathematical model of the pressure closed-loop control system is built,and the open-loop bode diagram of the pressure control system of the sealing ring test bed is drawn according to the transfer function derived,and the stability of the system is analyzed.On this basis,AMESim simulation software was used to build a simulation model of the pressure closed-loop control system,and the target pressure was simulated and analyzed.Through the analysis of the error characteristics of the system,it is found that the test index can only be achieved by adding the PID correction link,and the PID control parameters within the pressure precision range can be finally determined according to the target pressure value.In the control system research,adopts the pressure closed loop control way and the PID adjustment,not only the structure is simple,but also easy to realize in the project.Simulation results show that the closed-loop control system can meet the technical requirements in terms of response time and control accuracy,which provides a reference direction for future research in the same type of sealing ring test bench and other related fields.