Research And Application Of Detection Technology Of Lifting Wheel Bearing Of Running Gear For HXD_3C Locomotive

With the implementation of leap-forward development strategy in China's railway system,HXD_3C-7200 kW locomotives were equipped in some locomotive depots on a large scale.However,the monitoring on lifting wheel bearing of running gear for HXD3 C locomotive was not fully considered during its development,neither monitoring device installed nor detection method considered.From the operational situation in each locomotive depot,the lifting wheel bearing of HXD3 C locomotive's running gear was suffering an abnormally high failure rate,and the safety in production of railway passenger transportation was seriously threatened.Therefore,it was necessary to study the detection technology of the lifting wheel bearing of HXD3 C locomotive's running gear.In this paper,taking the abnormally high failure rate of lifting wheel bearing of HXD3 C locomotive as the starting point,research on the detection technology of running gear's lifting wheel bearing in garage was proposed.For this reason,the following main research work was conducted in this paper.?1?Through in-depth analysis on the computer control principle of HXD3 C locomotive and the size characteristics of axle-box of running gear,on the basis of current lifting set,adaptive improvement was made according to bearing size characteristics of HXD3 C locomotive.And detection technology of lifting wheel bearing was successfully realized.?2?When lifting the points of D1,3,4 and 6 in the detection course of lifting wheel axle-box,bearing velocity determination could not be realized.And there were serious problems of operational safety risks and data instability.Through further analysis of the root cause and comparison of technical routines,the scheme to determine bearing velocity with hardware was selected.According to the requirements of technical routine with hardware,a signal conversion device for bearing velocity determination of HXD3 C locomotive was developed.During the operation of the lifting wheel,the velocity signal of the Hall effect sensor on the motor side would be converted into that of photoelectric speed sensor at the axle end by this device,and then sent to the locomotive's control system.Therefore,a closed-loop control was formed so as to realize the stable control of the traction unit.?3?According to the actual situation,analysis demand on the data detection and diagnosis system was proposed.After that,the data sampling and analysis of eight channels could be conducted at the same time,and all measuring points on the whole wheel set could be detected only by lifting the wheel once,the velocity of wheel set was acquired and recorded as well.Meanwhile,a database storing data of various locomotives was established in the system.What's more,simple detection and precise diagnosis were combined to realize the complete acquisition of all measuring point on one wheel set,and the automatic judgment on the bearing status by software.?4?Referring to the threshold for lifting wheel detection of HXD1 C locomotive,a large amount of lifting wheel detection data was collected,analyzed,calculated and verified combing the disassembly inspection by manufacturers to the suspected failure bearings.And then the threshold of failure diagnosis for HXD3 C lifting wheel detection was gradually formed.