Rolling Stock Corrosion Control: Available Options and Implementation Issues

The Maryland Transit Administration (MTA) operates a fleet of 53 light rail vehicles (LRV) to support Baltimore’s light rail system. The first 35 LRVs entered into service in 1992. This set of rolling stock is constructed primarily of low-alloy, high-tensile steel with characteristics similar to ASTM A-588 steel. The as-built exterior roof sheeting was coated with an epoxy-based system to protect against weathering. Over the years the coating system performance has degraded and allowed moisture to seep underneath, resulting in corrosion. The corrosion is evident throughout the fleet and is progressively damaging the thin roof substrate. To address this issue, MTA commissioned Booz Allen Hamilton, the rolling stock engineering consultant for MTA, to assess the extent of the corrosion problem, research available solutions, and define implementation requirements. Information is provided on commercially available technologies, associated costs and benefits, and the unique challenges faced in implementing a long-lasting solution for in-service rolling stock vehicles.