Technical Reports

Test Results Report : Dual Disc/Tread Braking and Reduced Pressure Braking Evaluation Programs

  • 01
  • Mar
  • 1981
AUTHOR: D. Frankowski, R. Scofield
SUBJECT: Amtrak, Braking Systems
ABSTRACT: This report is the Test Results Report for the Dual Disc/Tread Brake Test. Data logs and records associated with this test are published separately in the Test Events Report Dual Disc/Tread Braking and Reduced Pressure Braking Evaluation Programs, Report No. FRA/ORD-8l/21. The Dual Disc/Tread Braking Test was conducted to investigate the benefits of using dual systems on the Amcoach. The test evaluated candidate systems developed by Knorr-Bremse, New York Air Brake and Westinghouse Air Brake Company. The test showed that as presently configured, the Amcoach may often exceed the available adhesion and tend to experience momentary wheel sliding which causes spalling. The test indicated that the dual brake system may help to improve tread life and extend the capacity without over heating either the wheel tread or the disc. In addition to the single car cutaway test of the dual brake system and a normal Amcoach braking system, a special reduced pressure test was performed on the Amcoach. The results showed that reducing the full-service braking pressure may be an alternative way of reducing the adhesion demand at the lower speed to relieve the wheel sliding problem. This approach extends the stopping distance by only a small amount but does not provide a mechanism for maintaining the wheel/tread surface or increasing the overall system capacity as does the dual brake system.