PIPING INSULATION AT THE CAORSO NUCLEAR POWER PLANT: PRE-SERVICE INSPECTION EXPERIENCE AND IN-SERVICE INSPECTION REQUIREMENTS.

The experience acquired during the baseline inspection of piping carried out at the Caorso nuclear power plant is described. At first the importance is emphasized, for a fast and inconvenience-free inspection, of an accurate documentation answering to well defined criteria. Much attention is given to the problems and difficulties encountered in the field, deriving from the piping insulation design and the different types of removable insulation used, particularly in connection with future in-service inspection requirements. The advantages and disadvantages of some types of insulation used at Caorso are discussed. The blanket type insulation is described, studied and adopted as an alternative to the rigid reflective insulation, where the latter turned out to be not suitable.