Ultrasonic Sciences - Ultrasonic Wheel and Axle Testing

Ultrasonic Sciences Ltd (USL) supply ultrasonic NDT systems (non-destructive testing systems) for inspection of rail wheels and axles, both during manufacture and in-service. Equipment is designed and manufactured in the USL factory, so we can tailor systems to meet your particular requirements, or design custom units for your specific application.

INSPECTION OF RAIL WHEELS –MANUFACTURING AND IN-SERVICE

Wheel inspection systems have been installed in manufacturing plant for both forged and cast wheels. In most cases testing systems are fully integrated into the production line, with communication between the ultrasonic units and the computers, PLC's and robotic handling systems in the manufacturing plant. These systems are normally configured for "Go/NoGo" evaluation of products based on national or international quality specifications, but they can provide graphic displays of the position and severity of defects.

For in-service inspection, a unique ultrasonic testing unit has been built for incorporation into an underfloor wheel lathe. This uses the hydraulic and mechanical systems of the wheel lathe to scan the ultrasonic probes over the wheels, thus removing the need for an independent mechanical system which would be complex and expensive.

INSPECTION OF RAIL AXLES – MANUFACTURING AND IN-SERVICE

USL's involvement in the rail industry started in 1988 with the development of mobile equipment for the in-service inspection of hollow axles. This continues today with supply of third generation equipment for recently introduced trains in UK. This equipment inspects the complete axle from one end with the wheelset in-situ on the train. Normally it is necessary only to remove the axle end cap to allow the test unit to be coupled to the axle (see photographs). In this way defects developing from the wheelseat, gear seat, brake disk seat or other hidden areas can be detected without removal of the components.

In these systems the results are presented in the form of a graphic image, known as a "C Scan", with any defects above the reject threshold highlighted. The inspection program is set-up to display defects according to the minimum criteria established by the design authority. Typically the inspection must identify defects on the external surface of the axle between 0.5mm and 2mm deep.

Systems for inspection of axles in the manufacturing plant use total immersion of the axles in water based couplant, with multiple probe assemblies scanning over the axle surface. Again, these systems can be fully integrated with the factory mechanical handling equipment.

Users of USL equipment include Bombardier Transportation, Alstom, Eurostar, SNCF, Lucchini and Indian Railways.