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Harry Skoblenick

Harry Skoblenick
Bombardier Transportation


Using Wheel Matching Technology to Create Conformal Profiles on Frogs at JFK Metro

The rolling surface profile found within standard AREMA railway crossovers, and in particular the manganese fixed frog casting, has been pre-defined for many years. If the supporting profile is worn, passage will be unstable with the vehicle wheel impacting the casting and leading to premature bogie failure plus accelerated track wear. Over the past 100 years, very little advancement has been published to explain how to precisely ‘wheel-match’ or improve the established frog designs already installed in the field. Recently, Conformal fixed frogs has entered the market but are supplied only for new applications and cannot be easily re-shaped to original condition if worn..

Without a process and guided mechanism to precisely shape the full-length of the crossover to match a specific wheel profile, and without an accurate means (template) to quickly and easily verify the profile slope provided after weld repair, instability to wheel passage (load impacts) and track / equipment wear will repeat and continue to re-occur.

Bombardier Transportation's new patented wheel-matching technology (WMT) provides the ability for track personnel to easily field apply a high-precision ‘conformal' surface profile over the full length of any new or existing standard crossover; precisely measure the accuracy of desired profile; and the ability to maintain the precision profile for life of the transit or heavy haul application.

The process and application of WMT have been developed and successfully tested on over 30 crossovers within the JFK Metro System over the last 36 months. The new product and process developed uses established competencies such as testing, analysis, welding and profile grinding.