Design And Research Of Hydraulic Control System In Drilling And Excavating Machinery

To achieve the function of drilling and mining, with hyundai225LC-7hydraulic excavator as host attachs to hydraulic impact machine accessories. With hydraulic excavator hydraulic pump as power source, accessory equipment hydraulic control system is designed, which mainly including impact circuit, rotating circuit, feed circuit and secondary circuit, the main circuit in the system is analyzed, and then the flow speed control valve of circuit is experimentally studied.Firstly, main action and working device structure in drilling and excavating machinery is analyzed, and the original hydraulic system having low drilling efficiency and reliability is pointed out, and then new hydraulic system is designed. Work efficiency of motor in rotation circuit of new hydraulic system is increased, and make sure safe during working by applying counterbalance valve in feed circuit of new hydraulic system. Thread cartridge hydraulic integrated block is applied, and three kinds of the rectangular channel pressure loss are analyzed by Fluent and then the channel of integrated block is optimized. According to the characteristics of feed circuit and rotating circuit match each other, improving the efficiency of drilling is researched.Secondly, the main circuit of hydraulic system is simulated and analyzed by AMESim. In hydraulic impactor model simulation, the effect of flow rate changes on the impact performance parameters is analyzed; In counterbalance valves of feed circuit model simulation, the results shows that the feed cylinder bearing static, weight lifting up and weight down are safe; In flow speed control valve mathematical modeling and model simulation, the old and new speed control loop hydraulic system adopt the overflow valve or pressure relief valve to overload protection is compared and the advantages and disadvantages are analysed, and then the causes of deficiency of rotary motor traffic is explained in the original plan.Finally, the hydraulic circuit of flow speed control valve is experimented, the experimental results are consistent with the simulation and the validity of the simulation model and the rationality of the hydraulic system are verified, the usage precaution for the flow speed control valve is summarized,...