Canadian Railroads > "Uphill slow, downhill fast"

Transport Canada Rail Safety Advisory Letter titled “Potential brake valve failures on cars that have been in long term storage”, issued subsequent to a "situation" last winter on the CN Luscar Industrial Spur in Alberta, aka the "Coal Branch".

Carmen  - armchair and otherwise - feel free to chime in;)

http://tsb.gc.ca/eng/medias-media/sur-safe/letter/rail/2018/r18e0007/r18e0007-617-04-18.asp



Edited 1 time(s). Last edit at 09/11/18 16:49 by xcnsnake.

Makes sense, after long storage nothing works right. Wonder where and what environment the coal cars were stored. Just like an automobile in long storage, gaskets dry out, contaminates settle and plug things, eventually when the auto is started it does not run right.
My two cents.
Doug

“Tonnage first, safety last”

The link tells us the issues:
 
“Testing had determined that worn rubber seals from the bottom cover exhaust port of the DB-10 service portions could shrink during extreme cold temperatures. This could then result in auxiliary reservoir leakage and lead to an unintended release of a service brake application.”
 
“With respect to the DB-20 emergency portions, the NYAB tests established that the failure mechanism was not the same as the failure mechanism for the service portions. For the emergency portions, the failure was related to a deformed K-ring inside the vent valve, which resulted in excessive leakage during extreme cold temperatures and the failure to propagate the emergency brake application command. The setting and deformation of the K-ring rubber had likely occurred when the coal cars were in storage for an extended period of time prior to being delivered to CN. With the permanent deformations, the intended performance of the K-ring, particularly during cold temperatures, was negatively affected.”
 



Edited 1 time(s). Last edit at 09/20/18 07:51 by ldstephey.