|A 1.4m research and development project aims to develop a lightweight robot for the automated inspection of nozzle welds in nuclear reactors.
The project, which is backed by EC funding, brings together Phoenix Inspection Systems, Peak NDT and The Welding Institute (TWI) in the UK with partners in France, Spain, Bulgaria, Lithuania and Greece. The partners aim to provide both existing and new-build nuclear power plants with a versatile inspection machine that will revolutionalise the pre-service and in-service inspection of plant components.
Nozzle sections in nuclear reactor pressure vessels are classed as critical components requiring thorough inspection to prove their integrity. Early detection of cracks is essential but there is a need for new systems that can reduce the time and cost of inspections.
NozzleInspect, as the project is known, aims to design an autonomous robot system that is able to reduce inspection times, improve defect detectability and sizing and reduce the need for human intervention which will in turn reduce the risk of radiation exposure by the workforce.
The project aims to develop a novel flexible phased array probe to allow a full inspection of nozzle weld areas with the same probe, and an advanced navigation system that follows the weld in the nozzle. The use of one phased array probe reduces the amount of manipulation required which consequently reduces the size and cost of the robot and helps ensure faster set-up and inspection times.
Phoenix is the lead SME on the project while PeakNDT and Vermon of France are sponsoring the development of the ultrasonic system, software and probes. KTU of Lithuania will be helping to develop the navigation system while Cereteth of Greece will be developing the robotic systems and TWI will be responsible for the phased array technology.
Hydraulic Elements & Systems plc of Bulgaria will be providing industrial nozzle weld specimens while Nexus, also from Bulgaria, will carry out field validation trials. Once completed, the NozzleInspect system will be trialed by Spanish utility operator Iberdrola.
Karl Quirk, managing director of Phoenix, said: Nozzle inspections pose a number of challenges which make such operations time-consuming and expensive. Given the number of ageing nuclear power stations currently in use, there is a need for faster, cheaper and more accurate inspection systems.
Our approach, which combines a new phased array inspection design with an advanced navigation system and low-cost robot, should reduce inspection time from 20 to 18 days per plant. With the cost of an outage at around 800,000 per day, this would represent a significant saving for operators not to mention the other benefits in terms of less human intervention and more accurate detection that the system will offer.
Phoenix Inspection Systems Ltd