LU is installed on the inspection line in the EMUs Depot. With inspection trolley running along the ditch,  based on combined utilization of phased array and conventional ultrasonic inspection technology and robotictechnology, it implements the fine, automatic and efficient scanning function for the wheels. The equipment can also automatically detect the defects of the wheel flange, wheel rim and wheel disk, which is suitable for on-line flaw detection of all types of EMU wheels.