रेलफैनों की तो बात ही कुछ और है

Not the intensity of the jerks, but the locomotive does have an effect on the coupler strain. Particularly in CBC coaches, the knuckle and the CBC lock are usually the most frequent points of failure. With the starting acceleration ( or rather, the high draw-bar forces at start) of the WAP7, any material defects in the coupler, can lead to an increased chance of the coupler breaking. In fact, during the 2005-2007 period, there were man cases of train parting due to CBC coupler failure. These were mainly due to material defects, but the problem was being worsened by the locomotives as well. While the failure rate has become very low now ( as is usually a problem only with freights), nonetheless, some internal buffer modifications had to be done to allow for higher drawbar forces.

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