Abstract:
It is well known that the main bolts in the Reactor Pressure Vessel (RPV) play significant roles in the nuclear power plants and other applications with nuclear power supply. The critical standards for inspecting these bolts have been established in RESM. Taking account into the complicated structures in the mechanical parts, electronic components and the ultrasonic detection systems, a new inspection control device has been designed to meet the stringent criterions of nondestructive testing, and it fulfilled the requirements for automatically inspecting. The implementation in the mechanical part could be sufficient for the circumferential and axial movements of ultrasonic detectors in the main bolts. The application of digital motion control (DMC) card and its relevant modules in servo motion controller accomplished closed-loops system. This inventive design promised a sufficient precision for the motor motion. The ancillary software for this control system greatly reduced the losses caused by human errors, improved the safety and practicality. This control system has been successfully used for the pre-service and in-service inspection in nuclear power plants.