Root Cause of Undesired Hose Separations and a Solution

Hose separations remain a significant problem for the class 1 railroads. They average about six thousand undesired hose separations a year. There are a lot of facts that the railroads are aware of, but lack good explanations. Why do more separations happen in the winter than in the summer? Why are old end hoses more prone to separation? Why does replacing the gaskets more frequently lead to a lower separation rate? Substantial research has been done to figure out the root cause of the undesired separation problem and to answer the above questions. The data analyzed from the class 1’s has shown that the trolley arrangement accounts for 52% of the undesired separations. The force to move the end hose in a cushioned car trolley arrangement is sometimes greater than the force required to pull apart the gladhands. It is probable that misalignment of the gladhands, coupled with an end of car (EOC) cushioning arrangement that hinders smooth movement of the end hose, will lead to an undesired hose separation. Research points to the fact that if there is a way that the force required to pull apart the end hose connections is kept greater than the force required to move the shackle on a trolley, then this will lower the frequency of undesired hose separations. By changing various characteristics of the gladhand gasket, it can be ensured that the pull-apart force is always around the 600lb range. These changes have been incorporated into the design of a double wide lip gasket and are currently in field testing. By reducing the occurrence of undesired emergency (UDEs) separations, the amount of time a train is stopped can be greatly reduced.