Dynamic identifying method for instant contact loss of wheel rail under impact effect of wheel rail

Abstract

The invention discloses a dynamic identifying method for instant contact loss of a wheel rail under an impact effect of the wheel rail and belongs to a traffic information safety technology. The dynamic identifying method comprises the following steps: firstly, mounting a vibration acceleration sensor above a wheel axle box; collecting axle box vibration acceleration information measured by the vibration acceleration sensor through a background collector; extracting a time-frequency feature for the axle box vibration acceleration, thereby obtaining a time-frequency distribution feature; and drawing a contour map for the time-frequency distribution feature and judging if the wheel rail instantly loses the contact. According to the scheme, the purpose of immediately detecting the ultra-large hidden danger of the instant contact loss of the wheel rail under the impact effect of the wheel rail is achieved according to the dynamic identifying method provided by the invention; the possibility of derailing of a vehicle is eliminated; the technology is mature; the reliability is high; the cost is low; the quantity of the channels is less; the system is simple; the anti-interference property is high; and the social and economical benefits are very obvious.

Description

technical field [0001] The invention belongs to the field of transportation, and in particular relates to a dynamic identification method for instantaneous loss of contact between a wheel and a rail due to the impact of the wheel and rail. Background technique [0002] When the rolling stock is in service, when the wheels are locked by emergency braking, if the wheels run on soft objects such as ice, snow, leaves, etc. on the surface of the rail, the rotational motion of the wheels changes from rolling to sliding or slipping motion, and the wheel rails will inevitably slide friction. Compared with the relative rolling friction, the sliding friction is severe, and the high temperature generated by the severe sliding friction causes wheel defects such as scratches, peeling, cracks and falling blocks on the wheel tread, and these defects bring intermittent blows and damage to the wheel-rail system . Existing theoretical calculations and experimental tests have shown that the ...

AI Technical Summary

Problems solved by technology

Existing theoretical calculations and experimental tests have shown that the wheel-rail impact force generated by defective wheels is several times that of the wheel-rail static load, and the high-frequency part directly has an adverse effect on the track and wheels, thereby reducing the service life of the vehicle and the line , increase energy consumption and increase maintenance costs, seriously cause the axle temperature to rise and cause the axle to sever;

At the same time, special attention should be paid to the fact that when the running speed of the rolling stock reaches a certain value and the size of the defect reaches a certain value, the wheel-rail impact will cause the wheel-rail to lose contact instantaneously, and some will cause the wheel-rail to lose contact intermittently for many times. The loss of contact means that the vertical force of the wheel and rail is zero, and the instantaneous derailment coefficient is infinite. For example, when driving fast on a road section with large lateral force such as a curved line or a super-elevated track, the possibility of derailment of the vehicle is very high.

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