Improvements for the stability of heavy-haul couplers with arc surface contact

ABSTRACT

To investigate the stability mechanism of heavy-haul couplers with arc surface contact, the geometry and force analysis were conducted according to the friction circle theory. To improve the stability of the coupler, four improvements were proposed, which are increasing the secondary lateral stiffness of locomotives, adding a restoring bumpstop at the end of the coupler, increasing the arc surfaces radii and changing the clearance and stiffness of secondary lateral stopping block. A multi-body dynamics model with four heavy-haul locomotives and three detailed couplers were established to simulate the emergency braking. In addition, the coupler yaw instability was tested to investigate the effects of relevant parameters on the coupler stability. The results show that increasing the secondary lateral stiffness of locomotives, adding a bumpstop with a smaller bumpstop gap, increasing the arc surfaces radii, increasing the stiffness and decreasing the clearance of secondary lateral stopping block are conducive to improving the stability of the coupler with arc surface contact.

KEYWORDS:

• Heavy-haul couplers
• coupler stability
• improvements
• locomotive
• derailment

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The material in this paper is based on work supported by grants (51675443, 51735012, 51405404) from the National Natural Science Foundation of China, Key Laboratory grant (2015TPL_T10, 2017TPL_T02) of the Independent Research and Development Projects, and Research Innovation Team grant (17TD0040) of Sichuan Provincial University.