Design And Simulation Analysis Of A Dual-Circuit Hydraulic Braking System For Wheel Excavator

Because of the relationship to the security of transitions walking and construction work, the braking system for wheel excavator attracts widespread great attention. Hydraulic brake system has the advantages of high output pressure, high component integration, smooth control and high stability, Thus it becomes the first choice of braking system for modern construction machinery vehicles. Although the low cost of the traditional pneumatic braking system and the gas-liquid braking system, the shortcoming of too many components, large space needed, serious pollution, low output pressure and high failure rate made it difficult to meet the requirements of lightweight, environmentally friendly and safety. Around the project of the company, a dual-circuit hydraulic braking system for wheel excavator is introduced. Two key hydraulic components of dual-circuit accumulator charging valve and dual-circuit hydraulic braking valve are designed for the system. The main work is as follows:1. Based on the overall structure of the wheeled excavator, calculating for the braking parameters, and proposes a dual-circuit hydraulic braking system.2. A dual-circuit accumulator charging valve is designed for the system, the valve uses the pressure feedback principle, the structures is designed. So that the charging valve priority for filling the accumulator, the accumulator maintain at the pressure range required, thereby improving the reliability of braking.3. A dual-circuit hydraulic braking valve is designed for the system, the parallel design principle is used, the structures is designed. So as to ensure the two circuits(front and rear axle) without interference to each other, and reduces the incidence of braking accidents.4. The simulation models of charging valve, braking valve and dual-circuit hydraulic braking system are established by the software of AMESim. The characteristics of filling pressure, filling flow and filling response speed are simulation analyzed. And the characteristics of braking pressure, braking response speed and braking force are simulation analyzed.5. In order to verify whether the design of the charging valve and braking valve meet the requirements of the braking system and the design standards, the verification experiment is did on the multi-function hydraulic test stand. The results showed that both valves are up to industry standards.