Development of a Passenger Wheel Standard

Abstract

The American Public Transit Association (APTA) is seeking to develop specifications to ensure that wheels used in passenger applications perform safely under the service conditions to which they are exposed. To this end, an approach has been developed which will address this need at two levels. First, a variant on the Association of American Railroads (AAR) S-660 standard [1] is proposed with loading requirements that more realistically represent typical conditions in passenger operations. This is considered a design standard and is to be applied to identify wheel designs not susceptible to fatigue cracking in the wheel plate and hub suitable for use by transit and commuter agencies. Second, an application standard (or more precisely, a recommended practice) has been conceived which is designed to assist transit agencies (or original equipment manufacturers) in the appropriate choice of an “approved” wheel design based on the expected service environment. This technique will identify wheel designs which, under normal operating conditions, should not result in thermal damage to the wheel tread.