Numerical simulation and experimental research on mechanical behaviour of hydraulic disc brakes based on multi-body dynamics

As a vital road construction machine, the bridge erecting machine works in a very complex environment. The brake as an important link to maintain the safety and stability of the bridge erecting machine, it will have serious consequences if it is failed. Establishing the brake simulation model and specifying the fault characteristics according to the actual operation status will make it more efficient to find the cause of faults and maintain the safety of machine for a long time. A simulation model of brake of the bridge erecting machine was established by Adams. The brake arms and center axis with obvious data characteristics were flexibly processed, and finite elements were analysed using Abaqus. To verify the accuracy of simulation models, rectangular rosettes were applied to special geometric points, and the strain data were gathered by using the DH3816N collector and compared with the simulation model. The Adams kinematic simulation model was used to simulate the actual operating conditions by the experiment of the disc springs. Two typical fault phenomena were selected: reduced insufficient of disc spring and oil pressure, and two fault characteristics were extracted: variation of the brake shoe clearance and variation of the braking system pressure. When the brake generates the fault characteristics, the normal operation of the brake will not be affected if the fault characteristics are in the first stage. When the fault characteristics are beyond the critical threshold, the faults phenomena of the brake are generated. The results of the simulation experiments proved that the method of using the simulation model to extract the fault characteristics of the braking system and distinguish the causes of the fault was feasible.