Ultrasonic Detection of Rail Faults

Railroads have long been interested in finding hidden rail defects before rail failure can cause a very serious train derailment. Early rail fault detection methods employed magnetic detection principles, later being supplemented by ultrasonic rail fault detection systems. Most rail fault detection equipment was housed in a large, heavy rail or road/ rail vehicle that required revenue trains to relinquish right-of-way to the test car. In 1974, the Santa Fe Railway broke with tradition and produced an experimental, light weight road/rail test car using a sophisticated ultrasonic rail fault test system. The experiment was so successful that eleven more cars were produced and placed in operation. Now entering its second generation, the Santa Fe ultrasonic rail test cars number twelve. The car is a standard Chevrolet Suburban, Model C-20 modified to carry 120 gallons of couplant liquid, electronic test equipment and a crew of three. Hy-Rail equipment has been added to provide road/rail operation. The test car is very mobile both on and off the rail, therefore, revenue trains need not be delayed. The cars are dispersed throughout the Santa Fe rail system so that the car is close to its home shop, reducing maintenance problems and providing a suitable home life for the crew.