Study On Reliability Of Emergency Braking Performance Of High-speed And Heavy-load Monorail Crane

The coal mine transportation system is mainly divided into the main transportation system and the auxiliary transportation system.The main transportation system undertakes the coal transportation task,and the auxiliary transportation system undertakes the personnel,equipment and material transportation task.As a new auxiliary transportation equipment,monorail crane has the advantages of convenient roadway layout,high transportation efficiency and strong mobility.Due to narrow roadway space and changeable roof conditions in coal mines,the requirements for emergency braking performance of monorail cranes are very strict.Research on the braking system of monorail cranes with high safety and reliability is of great significance for improving mine production safety and reducing the occurrence of malignant accidents.Taking the DC200/190 Y explosion-proof diesel engine monorail crane as the research object,based on the multi-body dynamics,thermodynamics and reliability theory,the emergency braking performance of the monorail crane under different working conditions is studied,and the thermal-structural coupling characteristics of the brake friction pair are analyzed,and the reliability evaluation of the monorail crane under emergency braking conditions is carried out.(1)Based on friction and wear tests and theoretical analysis,key parameters such as brake friction coefficient,spring stiffness,and spring preload of the monorail crane were obtained.Dynamic models of the monorail crane under various operating conditions such as horizontal straight rail,vertical curved rail,and horizontal curved rail were established.The emergency braking characteristics of the high-speed and heavy-duty monorail crane under different operating conditions were studied,and the spring stiffness The influence of braking clearance and friction coefficient on the emergency braking characteristics of monorail cranes.(2)A thermal-structural coupling model for the brake friction pair of a high-speed and heavy-duty monorail crane was constructed,and the variation laws of the temperature and stress fields of the brake shoe and rail under emergency braking conditions were analyzed.The influence of the changes in parameters such as brake pressure,friction coefficient,initial brake speed,and brake shoe area on the thermalstructural coupling characteristics of the brake friction pair was investigated through the control variable method.(3)Combined with Latin hypercube test design and DD(Dendrite net),the nonlinear random response models of braking distance and braking temperature of monorail crane with random parameters are constructed respectively;Based on the saddle point approximation theory and Sobol sensitivity analysis method,the reliability evaluation of the emergency braking performance of monorail crane is carried out,and the influence of various random parameters on the reliability of the emergency braking performance is studied.In this thesis,there are 92 figures,16 tables and 89 references.