Justification for reducing the weight of the frame of the platform car for transporting containers in modular electric freight trains

Abstract

Background: The article describes the rationale for reducing the metal content of platform cars of a modular electric freight train (MEFT) due to the distribution of traction power across the composition and reducing internal kinetic forces in the train. The calculation of the volumetric model of the car frame under the action of the weight of containers and quasi-static load, the analysis of the distribution of equivalent stresses is made. The effects of introducing these types of wagons into modular electric freight trains are considered.
 A railway train of locomotive traction is a complex mechanical system in which dynamic processes occur due to the traction force of locomotives, fractures of the profile and track plan, braking and releasing the brakes, different rates of pressure change in the brake line, and uneven resistance to movement of the locomotive and cars [1]. When driving the MEFT formed a much smaller amount of internal kinetic energy, allowing to reduce the load limit on the hitch and the frame of the wagons to transport more cargo with equal traction power by reducing the coefficient of tare of the train. In addition, running MEFT will improve the handling and safety of trains, reduce operating costs for passing train flows by reducing energy consumption for traction, braking, reduce the time for testing the brakes, the number of car, locomotive and crew hours. We predict significant (up to 7 times) reduction of loads on the coupling devices and the frame of cars, if the strength condition is met.
 Aim: To justify the possibility of reducing the loads on the auto-coupling equipment and metal structures of the frame of platform cars as part of modular electric freight trains by reducing the longitudinal forces in the auto-coupling devices due to the distribution of traction power across the composition.
 Methods:
 
 special engineering methods for traction calculations applied to railway transport;
 engineering and technical methods of calculation and design of platform cars;
 finite element method;
 a system method that allows you to identify various direct and indirect relationships in the analysis of the selection of frame structures of platform cars.
 
 Results: We justified reduction of loads on auto-coupling devices and load-bearing frames of platform cars in MEFT. It is revealed that the decrease of axial compressive loads on the automatic coupler device with 2,500 kN in the car locomotive hauling up to 400 kN at the car the IAEG will help to alleviate the weight of the metal frame of the wagon-platform for transportation of containers and reduce packaging of the car is 1.6 t, by 7.3 %. The reduction in the cost of the car will be 76.8 thousand rubles, or 3.84 %.
 Conclusions: The author offers a justification for reducing the weight of container cars-platforms of a modular electric freight train, on the basis of which it is possible to reduce the metal content of cars and transport a larger amount of cargo with equal traction power in comparison with a train of locomotive (concentrated) traction.