Research On Performance Of Multiple Friction Mechanisms And TPEE Component Combination Draft Gear

As an important component of shock absorption in railroad transportation,draft gear can ensure the safety of trains and cargoes during transportation.The research object of this paper is a combination of various friction mechanisms and polymer elastomeric elements(TPEE)draft gear.The design of the friction mechanism is increased to increase the friction loss of the draft gear in order to improve the capacity and energy absorption rate of the draft gear.The difference in the number of layers of the moving plate mechanism as well as the wedge mechanism of each draft gear design scheme makes the performance of stroke,capacity,and energy absorption rate different.This paper analyzes and compares the performance of various combined draft gears to determine the more superior design solution.The research in this paper is as follows:(1)The working principle of TPEE combination draft gear is introduced,and the kinematic equation is derived for the friction mechanism.Later,the hydrostatic test is conducted on the TPEE component part to obtain the correspondence between its force and displacement,and finally the theoretical solution calculation of the combined draft gear is completed.(2)Various types of superelastic and viscoelastic intrinsic models were analyzed,and the data obtained from uniaxial compression experiments on TPEE materials were used to obtain an intrinsic model that basically conforms to the TPEE material of polymer elastomer and expresses the super-viscoelastic properties of the material.And the simulation of hydrostatic test is carried out for TPEE component part to prove the accuracy of the intrinsic model.(3)According to the standard TB/T1961-2016 of the Ministry of Railways,a variety of combined draft gears are simulated in static pressure test,and the simulation results are compared and analyzed with the theoretical settlement results,and then the working parameters such as stroke,capacity and energy absorption rate of multiple draft gear design solutions are compared and analyzed to determine the more superior design solution.(4)According to the Ministry of Railways standard TB/T1961-2016,the TPEE elastomer draft gear was subjected to drop hammer test,and then the TPEE elastomer draft gear,the one-layer wedge mechanism draft gear with driving plate and the two-layer wedge mechanism draft gear without driving plate with similar performance were subjected to drop hammer test simulation and comparative analysis to determine their working parameters could meet the design requirements.This paper combines theoretical calculations and finite element simulations with experiments to compare and analyze the performance of various combination draft gears,and proves that the finite element simulation method is more reliable to study the performance of draft gears.In addition,the study can provide ideas for the development of combined draft gears for different applications,and provide reference for the optimization of the structure of cargo draft gears and the manufacture of prototypes.