Operating tank cars in North America presents significant logistical and regulatory challenges. With several hundred thousand cars in service, each requiring detailed inspections every ten years under stringent safety standards, operators face considerable time, cost, and operational downtime. Among the most critical and labor-intensive tasks is the inspection of structural welds located on the lower, high-stress areas of the tank car. Traditionally, this inspection has relied on Magnetic Particle Inspection (MPI)—a method that requires coating removal, chemical application, post-inspection cleaning, and recoating. The process is time-consuming, environmentally taxing, and difficult to audit, introducing inefficiencies and potential reliability concerns.
This presentation explores how these challenges have been addressed through the implementation of Alternating Current Field Measurement (ACFM) technology, coupled with the development of custom probes and intelligent software tools. Beyond the technical shift, we will highlight how process optimization—honed over multiple deployment cycles and real-world experience—has played a crucial role in transforming the inspection workflow.
As a result, what once took approximately 8 hours per tank car can now be reliably and repeatably accomplished in as little as 30 minutes. The new approach not only improves speed and reliability but also enhances auditability, reduces environmental impact, and supports more sustainable maintenance practices. The paper will also share insights from recent field implementations and discuss the collaborative innovation that continues to drive further improvements.