Electronic Air Brakes for Trains

Starting in mid-1993 Burlington Northern Railroad’s (BN) Corporate Applied Technology and Mechanical Departments initiated discussions with TSM, Inc., a Kansas City based railroad supply company, concerning the development of electric freight train brakes for BN application. This was the first-time effort to apply an overlay system to the conventional freight train brakes to provide the following benefits: • Better train control and shorter stop distances for heavy haul coal, grain and intermodal service • Increased average freight train speeds and reduced line congestion (greater line capacity with reduced headways between trains) • Significant reduction in wheel wear and thermal cracked wheels due to uniform braking (reduced operating costs and enhanced safety) • Reduced train slack action with graduated release and elimination of undesired emergencies BN and TSM formed an agreement for testing of Electro-Pneumatic (E-P) brake equipment (up to 65 coal cars) starting at Beardstown, IL in September 1993. The first-ever successful U. S. operation of E-P brakes for freight train application (30-car train) was accomplished in BN’s revenue coal train service on December 9, 1993 operating between Beardstown and the Crown Two Mine at Virden, IL. It was soon followed by a successful test of a 65-car coal train in April 1994. Since that time BN/TSM has operated additional durability tests of the E-P brakes in this same service on the full size 65-car. The results of the first TSM tests indicated an approximate 40% reduction in stopping distance (full service brake stopping) and slightly reduced emergency stops. The equipment operated well as an overlay to the existing air brake system throughout winter and summer testing. Engineers’ responses to the equipment were favorable, especially related to the capability of graduated release of the brakes and the overall train control.