Ultrasonic profilometry system for control rod wear

This patent describes an apparatus for scanning the outer profile of control rods. It comprises a module support positioned at a fixed location with respect to a control rod to be scanned, a transducer drive tube mounted for rotation about the axis of a control rod for receiving a control rod therein, a transducer holder connected to the transducer drive tube carrying ultrasonic transducer means facing an interior of the transducer drive tube, for sending an ultrasonic beam to and receiving ultrasonic echo energy from the surface of the control rod, the holder having at least one part for carrying the ultrasonic transducer means which is mounted for limited radial movement with respect to the transducer drive tube; rotation means, mounted to the module support and engaged with the transducer drive tube for rotating the transducer drive tube and the ultrasonic transducer means around the axis of the control rod; and translation means for translating the control rod with respect to the ultrasonic transducer means, in a direction parallel to the axis of the control rod, for scanning the surface of the control rod along a helical path