Research On Safety Boundary Of Braking Process Of Electric Gravitational Wagon Retarder

With the development of heavy load and high speed in railway freight of China,the demand for deceleration and parking technology for the wagons in station is getting higher and higher,and the electric gravity type wagon retarder is an important equipment used in the railway freight,it is mainly used in the hump marshalling yard and the railway station,and it plays an important role in the hump marshalling station and the speed control operation of the traffic station,this paper presents a study of its braking performance and safety.In this paper,the TDDH00 electric gravity type wagon retarder designed by the Harbin Railway Bureau is studied.There are three key points of the study: One of the purposes is to study the influence of each parameters of the carriage and the retarder on the braking performance,so that their corresponding relationship can be expressed by mathematical modeling,the parameters of the carriage include the weight and the initial velocity,the parameters of the retarder include the friction coefficient and the braking-rail distance;the second purpose is to study the change of the position of the mechanism during the retarder is set with different initial parameters;and the third purpose is to analyze the cause of the wheels jumping when the retarder is used.Structure and working principle of the retarder are analyzed and studied in detail,combining with the summary of the data tested in the station field,and the investigation of the actual use of equipment,this paper presents a new idea about the contact form between brake track and wheel during breaking progress,it can be conjectured that the brake rail contact with the wheels by the point,on this basis,a new modeling to calculate the breaking-energy height is built,and it is verified through mechanics modeling analysis combined with the software simulation analysis,and the contact force between the brake rail and the wheels can calculated more accurately,and makes a more precise explanation for the possible phenomenon of wheels jumping.The brake pressure of braking-rail can be clearly confirmed through the analysis of the whole system consists of the vehicle and the stock rail,the road pillow,the ballast;the relationship between the braking-rail distance and the height of braking-rail and the uplift height of the stock rail is clarified through the kinematic modeling analysis of the reducer;Finally,the high braking-energy height is calculated,and the calculation of the braking energy is influenced by the distance of the braking rail,the friction coefficient,the height of the brake rail,and the uplift height of the stock rail synthetically.The braking-energy height can be calculated without any experience correction coefficient through the new mechanical model,and the braking-energy height is in accord with the actual changing rules of various parameters and the result is similar to the results tested on the station.According to the whole analysis and modeling process,a automatic computing software is developed through the Matlab platform.The station staff can verify the parameters of the retarder by the software,and also facilitate the rapid design of a new generation of products by the equipment development designers.