DEVELOPMENT OF VISUAL INSPECTION TECHNOLO GY FOR HTTR CORE SUPPORT GRAPHITE STRUCTURE

The Japan Atomic Energy Research Institute is now constructing the Hig h Temperature Engineering Test Reactor (HTTR), which employs a visual inspection of core support graphite structure, as an inservice inspect ion (ISI). In this inspection, TV camera will be used to investigate t he alignment and integrity of the structure. Therefore, the ISI system , a combination of radiation tolerant TV camera and graphic processing system, is developed and examined its detectability and viewing angle s using a simulated hot plenum of HTTR, which has artificial defects. As a result of a series of tests, it was confirmed that this system sa tisfied the requirements and was quite applicable for the ISI system o f HTTR core support graphite structure. In addition, further improveme nt of the system, like a remote control procedure, will be investigate d.