Research on the anti-impact characteristic of hydraulic luffing system on mobile crane

The simulation software AMESim was applied to build the hydraulic system model of the upper part of 25T mobile crane. And the characteristics of the multiple-unit valve and the counter-balance valve were simulated and analyzed. Then more research was carried on the luffing system. Based on the simulation model of the boom and key components of the luffing system, the parameters of the luffing system were modified and tested to recur the abnormal working conditions of the mobile crane, such as the unstable flow rate, the pressure impact and the unstable boom swing while the valve has a little opening. Then the luffing system of the crane was analyzed and simulated and several modifications were carried out to the multi-way valve of the luffing and the counte-rbalance valve. After modified, the luffing system was experimented on a real crane truck and the testing data was collected on site. The experimental results showed that the above-mentioned problems could be reduced efficiently after modification. The test results were in accordance with that of the simulation, which verified the accuracy of the simulation model.