Systematic characterization of component failures for the DIII–D tokamak

Abstract A fusion reactor will be a fairly complex system consisting of many components. All the components are required to produce plasma and control it. Some of the components will be large, and for economic reasons, there will not be spares for all the components. It is therefore important to have a system whereby troubles are communicated, recorded and analyzed. Such a trouble report system has been in place at the DIII–D tokamak facility for many years. The purpose of the system is to easily facilitate communication between the people that discover problems and those that fix the problems. The trouble sheets are logged into a computer database that is used to characterize the kind of problems that the facility experiences, and determine which equipment, software, or human errors are causing significant downtime. The information is also used to evaluate whether sufficient maintenance is done to the equipment and to provide a basis for replacing it. The original system was based on paper forms. Before the end of its first year in operation, the system was changed to a web-based system. In the new system a trouble report is filled out using a web browser, and the information is emailed to the repair personnel and managers as soon as the form is submitted through the web. The study will discuss the problems experienced at the DIII–D facility, and how the information is used to adjust the preventive maintenance schedule.