Open pump control hydraulic system of forging oil press

The huge energy consumed in the forging industry and the pollutants it emits into the atmosphere have always been the problems and difficulties that must be solved in the process of industrial development in China, and also the prerequisite for the realization of sustainable industrial development. With the proportional valve control system, closed type pump control system, the direct drive volume control electro-hydraulic servo system, compared with open pump control forging hydraulic press hydraulic control system can reduce the installed power, reduce the cooling oil filling system and simplify the system structure, to promote energy saving effect obviously, and retain the traditional system response is fast, the advantage of high precision and stability.

For forging industry, it is of great theoretical significance to study the volume control characteristics of the hydraulic control system of open pump-controlled forging hydraulic press, and it is of positive practical significance to apply the hydraulic control system of open pump-controlled forging hydraulic press in free forging, die forging, multi-direction die forging and other equipment. The load and process conditions of forging hydraulic press are time-varying and random, so the hydraulic control system is required to have good control characteristics under different load and process conditions. Based on the open pump control forging hydraulic press system as the research object, adopt the method of combining theoretical analysis and experimental research, with proportional variable radial piston pump, hydraulic press system and forging load time-varying characteristic as the foundation, in view of the open type pump unloading impact control forging hydraulic press system, load vessel independent control, piping system to study the dynamic characteristics of control, analysis of control system Fabrication method and response characteristics. The pressure relief impact problem of open pump-controlled forging hydraulic press system was studied, the pressure relief curve mathematical model was established according to the law of energy and flow, and the characteristics of different pressure relief curves in different pressure relief stages were analyzed.

Based on the different demand of pressure drop gradient in different stages, the combined pressure relief curve of open pump-controlled forging hydraulic press was proposed, and the variable pump eccentricity was planned to realize the steady pressure relief of the system. The independent control of load chamber in open pump-controlled forging hydraulic press system is studied. A load cavity independent control model for the composite control of master cylinder position and return cylinder pressure was established, and the influence of the coupling between master cylinder system and return cylinder system on the position control accuracy of movable beam was analyzed. A feedforward load synchronous compensation decoupling control method was proposed to improve the position control accuracy of fast forging system. The dynamic characteristics control of piping system of open pump-controlled forging hydraulic press is studied.

The hydraulic press system model containing the pipeline was established, and the frequency domain characteristics of the system were analyzed. A feedforward compensation control method based on the compound control of flow and pressure was proposed, which integrated the load characteristics of forgings, and improved the insufficient pressure reduction caused by the slow pressure rise during the fast forging process of the pipeline system. The effectiveness of the proposed combined pressure relief curve control method, independent control method of load cavity based on feedforward synchronous compensation decoupling control, and dynamic characteristics control method of pipeline system based on flow and pressure composite control were verified by experiments on 0.6MN forging hydraulic press experimental platform

this is  pump control hydraulic system forging produed by tongxin precision forging company: