Multiaxial Fatigue Strength Analysis Of The Locomotive Wheel

Wheelset is one of the important parts of locomotive vehicle bogie. When locomotive vehicle runs, the wheel should not only bear the huge mechanical load, and also brake thermal load in the way of tread brake and other brake. The load is very complex and working environment is relatively bad. In order to guarantee the safe operation of the vehicle, it is necessary to conduct the thorough research to the wheel fatigue strength.This paper refers to rule of Sines, rule of Crossland and rule of Dang Van (three multiaxial fatigue criteria) of wheel fatigue strength calculation, study the calculation of standard features. At the same time, this paper studies the influence factors of thermal load strength of the wheel, through to the mechanical load and thermal-mechanical coupling load under the action of wheels strength comparison analysis.The main conclusions of research are as follows:The thermodynamic analysis shows that wheel tread in the process of braking temperature after a sharp rise in slow decline. Heat contact surface mainly gathered in the tread and brake shoe, rim part due to the effect of heat transfer temperature rise, radial plate and the wheel core temperature did not change. Wheel produces the highest temperature, equivalent thermal stress and suffered most when brakes after 20 s.Static strength analysis shows that the wheel disk hole, wheel heart which cooperate with shaft and wheel disk which is hub transition zone are the most dangerous areas. The maximum Von mises equivalent stress values occurs in curve operating conditions, shows the most dangerous route is curve operating conditions, switch operation takes the second place. Under the thermal-mechanical coupling effect, wheel disk principal stress value is negative, namely the larger compressive stress.Fatigue strength analysis shows that safety factor choosing Sines criterion to assess is the minimum, rule of Crossland takes the second place, and Dang van criterion calculation of safety factor is the largest. So on wheel disk with a hole in the wheel of multiaxial fatigue strength check, by means of the criterion of Sines calculation should be safe. By Sines safety factor choosing Sines criterion to assess is the minimum, rule of Crossland takes the second place, criterion is the key node values is generally small, due to the rule of Sines focuses on the mean value of each node hydrostatic stress may make the calculation result is too conservative, contributes to appraise the result. Because of the effect of brake thermal stress, when carries on the multiaxial fatigue evaluation, increase the equivalent stress value at every point on wheels, but is very small, in engineering applications, for the simple calculation can not consider the effects of heat stress on wheel fatigue strength.