The Research About The Effects Of The Damping On The Dynamic And Static Characteristic Of The Wheel Crane Hoisting Hydraulic System

Hoisting mechanism is one of the most key subsystems in the wheel crane, and the performance of its hydraulic system is an important index of evaluation of the whole machine performance. Improving the dynamic and static characteristics of hydraulic system has always been the pursuit goal. therefore, the study of hydraulic system of hoisting mechanism is of great significance. This paper based on a type wheel crane in the practical work of the jitter of decline and secondary slide phenomenon, to improve the original hydraulic system, mainly the following work has been done to improve the performance of the hoisting mechanism.Firstly, the principle of the hoisting mechanism of wheel crane is analyzed, the types of hydraulic system of hoisting mechanism are study and this paper analyzes matching relation of the opening time between balance valve and brake cylinder. Through set damping network in front of balancing valve to make the turn on time more reasonable.Secondly, the internal structure of balancing valve is analyzed, and its mathematical model is established. This paper builds the simulation model of balance valve in the Hydraulic Component Design library of simulation software AMESim, and verifies the correctness of the model. At the same time, this article sets the simulation model of brake and verifies the correctness of the model.Thirdly, using the simulation software AMESim sets the model of the original hydraulic system, and the original hydraulic system is simulation respectively on the drop in working condition, load mutation condition and secondary lifting condition. Through the analysis of simulation results, it is concluded that the original system has the problem of decline jitter and secondary slide.Finally, this paper makes the following improvements to the original hydraulic system according to the previous analysis: aiming at the problem of decline jitter, this paper sets up a damping network which is composed of type C half bridge and one-way valve parallel, and simulation the improved hydraulic system, through the analysis of simulation results shows that the improved hydraulic system effectively inhibited the decline jitter; Aiming at the problem of secondary slide, this article sets up a damping network which is composed of two damping series first and then with a one-way valve parallel, and simulation the improved hydraulic system. The simulation results shows that the improved hydraulic system effectively inhibited the secondary decline phenomenon.