Experiment And Finite Element Analysis Of Tribology Performance Of Braking Material Used On Ultra High Speed Elevator

Safety gear is the emergency brake components of the elevator,which is extremely important to elevator.Nowadays,the better braking performance is required as the operation performance is improved.Focusing on high speed elevator braking period,this thesis mainly studies the friction behaviors,wear mechanisms and temperature rise characteristics of new braking materials,which provides a basis for the selection of braking material used in ultra high speed elevator.In this thesis,an elevator safety gear braking testing rig is established to simulate the ultra high speed elevator braking situation.The friction behaviors,wear mechanisms and failure modes under different working conditions are explored to comprehensively understand the internal mechanism of braking interface.Meanwhile,an finite element model is set up to explore the temperature rise of braking material.Firstly,an ultra high speed elevator safety gear braking testing rig is established in this thesis.The operating principle of testing rig is to drivethe inertia system and the brake disc rotate by motor.After triggering the safety gear,two braking materials make contact with the braking disc and finally stop the entire system.The brake disc in the testing rig is equivalent to the guide rail in the actual elevator.So,the braking interfaces are provided with braking disc and two braking materials,which are corresponding to the braking interfaces of guide rail and the wedges in real elevator system.In addition,data acquisition systems are set up to monitor the state of braking system,such as rotation speed,braking pressure and temperature etc.Then,the experimental scheme is designed to compare the friction behaviors and wear mechanisms of Cu-based powder metallurgy material and short carbon fiber reinforced material under different working conditions.The failure modes of braking materials are also analyzed and predicted.So the friction mechanisms of the braking interfaces are tried to explore and study.Finally,due to some difficulties of measuring the friction interface temperature of the braking materials,an finite element model is established by investigating existing literature.The simulation results and experimental results of are compared to predict temperature rise ofmaterial surface,which provides experimental data and theoretical guidance.