Technology Digests / Brake System End-of-Car Arrangement Tests

TD22-011

June 1, 2022
Authors
  • Yi Wang
  • Scott Cummings
  • Travis Gorhum
  • Matt DeGeorge
  • Mitch Miller
Share

Key Findings

  • End arrangements in the as-built condition, regardless of style, performed sufficiently in the laboratory environment and did not cause hose separation or brake pipe leakage.
  • Tests conducted in non-optimal conditions while mimicking common dysfunctionalities suggested that end arrangements equipped with trolleys were more prone to hose separations.
  • Test results showed the two most important mitigations for end-arrangement-related AHS and AHF included: .Choosing an end arrangement design that maintained a high level of functionality over the service life of the car and minimized the opportunities for incorrect field application or repair. .Performing correct repairs.

Brake System End-of-Car Arrangement Tests

MxV Rail (formerly TTCI) conducted end hose separation tests using a test rig that simulated the end-of-car hose arrangement installations (end arrangements). These end arrangement tests, funded by the Association of American Railroads (AAR) Strategic Research Initiative (SRI) program, reflect MxV Rail’s continued efforts to help mitigate service interruptions caused by air hose-related line-of-road failures (LORF). Air hose separation (AHS) or air hose failure (AHF) LORF is a major cause for undesired emergency brake applications (UDE) on trains, resulting in considerable service interruptions. In the case of an AHS, the end hoses must be recoupled by the conductor before the train can be recharged for departure. In this Technology Digest, a UDE resulting from substantial leakage at the end-hose-to-end-hose connection will be considered and referred to as an AHF. In a no-cause-found AHF event where the air on the train could be recovered immediately, railroads could still have operating instructions…