Study into vibration effects due to the wheel-rail interaction on the operation of an 3ES5K electric locomotive gear transmission under conditions of mountain pass traversal

The aim of the present work is to carry out an experimental study of vibration occuring at the nodes of the electric locomotive wheel and motor unit during motion in small radius curves (R = 250-350 m) of a mountain-pass section (with gradients up to 17‰). The vibration measurement was carried out experimentally at the 3ES5K Ermak electric locomotive using AR-2038-10 and AR-2038-100 vibration transducers mounted on the axle box of the first wheel pair, gear cover and traction engine frame. A specially designed system was used to continuously record the signal from vibration transducers over eight channels with a sampling frequency of 12.8 kHz. Experimental data on the parameters of vibration occurring the specified locations of the electric locomotive were are obtained during the wheel-rail interaction of the electric locomotive on an almost jointless trajectory of small radius curves. The level of vibration at the entrance to the small radius curves along the three coordinates of X, Y and Z was established to be almost an order of magnitude higher than outside the curve. In the case of traction mode operation of the electric locomotive, a sharp increase in the amplitude (up to 10 times) of harmonics with multiples of the gear frequency was shown to be caused by a coincidence with the natural frequencies of the gear cover. In coasting mode, in the frequency region of about 1.5 kHz, a pseudo-random vibration is recorded on the axle box with the RMS acceleration value of above 100 m/s², which is comparable to the acceleration values when passing a junction. The obtained data of the vibration parameters suggest the reliability of locomotives operating in mountain pass areas having many small radius curves to be significantly less than for flat area operation with the alternative of a jointless trajectory representing ineffective measure of reduction vibrations in small radius curves.

electric rolling stock, vibration, wheel-rail system, wheel-motor unit, vibration impact, small radius curves