Research On Adaptability Of Coupler Systems On33T Axle Load Heavy Haul Locomotive

The increase of train length and axle loads is the development trend in the heavy haul transportation. But longitudinal in-train forces become larger and larger during the development of heavy haul trains, some derailment accidents also occurred in these years. According to the accident analysis, several accidents were caused by larger coupler rotation angle under high coupler compressive forces which could generate large lateral components of coupler forces to wheelsets, and cause the rail widening and derailment accidents. Under this background, this paper combines the design work of33t axle load AC drive locomotives, the adaption of two typical types heavy haul coupler systems, which are called13A type coupler systems and102type coupler systems, to33t axle load locomotives, the coupler systemsMain research work and conclusion are as follows.1) Through the researches of domestic and foreign coupler and draft gear systems, detailed and accurate coupler systems universal model have been established, which can simulate13A type coupler systems and102type coupler systems by changing characteristics. The universal model includes coupler knuckle, friction surface, the stable structure, draft gear’s impedance characteristics and hysteretic characteristics. The coupler system models are also verified by the structural analysis and dynamic simulation.2) This paper establishes and verifies the new type33t axle load locomotive model, and then the’1+1’configuration20000t heavy haul train dynamic model have been developed base on the detailed coupler systems and locomotive model. According to this train model, the operational behaviors of two kinds of coupler systems and their effect to locomotive have been studied under idle, traction and braking conditions, the track is the tangent track and curved track. The locomotive equips with the13A type coupler has better operational behavior than that equips with the102type coupler on the tangent track, because the13A type coupler tail has friction surface which constrains the rotational behavior of coupler to a very small angle. On the curved track, the carbody occupies the tangent direction of curve and leads the rotation of coupler, the performances have distinct differences compare with that on the tangent track, the performance of locomotive is also worse. But the locomotive equips with two types of coupler can safely operate under three conditions. Simultaneously, combines with the structure analysis, the carbody stable mechanism has been analyzed according to the rotational behavior of the102coupler under braking condition. The results have guiding functions to study the behavior of round-pin coupler which is similar to102type Coupler.3) The maximum compressive capacity of the locomotive equips with two types of coupler has been analyzed using three-locomotive model. On the tangent track, the locomotive equips with13A type coupler system can endure2500kN maximum compressive force, but if the friction surface doesn’t work, the locomotive can only endure1000kN maximum compressive force; When the free-angle of102type coupler are8°nd6°, the locomotive can endure1000OkN and2500kN maximum compressive force. On the curved track, there is a large lateral component force generates by the13A type coupler, which increases wheelset lateral force of locomotives. At this condition, the locomotive equips with13A type coupler can only endure1000kN compressive force; When coupler free-angle of102type coupler is3°,4°,5°and6°espectively, the locomotive can bear2500kN,1750kN,1250kN and1000kN maximum compressive forces, respectively. At last, the operational safety margin of locomotive has been researched on curved track on different radius curves which have guiding functions to the operational safety of the train.4) Aimed at characteristic parameters of these two types of coupler, such as coupler slack, draft gear stroke, impedance characteristic and preload etc, the effects of parameters to train longitudinal impact have been studied, while the draft gear safety margin has also been analyzed. At last, this paper gives some suggestions to the type selection and parameter setting of coupler systems in the heavy haul train.The research indicates that to the33t axle load AC drive freight locomotives, the existing13A type coupler system still can be adopt, but the static impedance characteristics and maximum impedance force of QKX-100draft gear in13A type coupler systems are rather small; the existing102type coupler systems also can be adopt, and have relatively stronger adaptability, but its NC390draft gear’s maximum impedance force is too larger even exceeds the structure strength of carbody, and need to Match the energy absorption device. When developing coupler systems on33t axle load heavy haul locative, the coupler systems can basis for102type coupler with coupler shoulder devices, but they need to reduce the maximum impedance force. At meantime, the free-angle set should combine with the locomotive structure characteristic.