This paper presents two proposals of norms (standards) which have been discussed by a Working Group of UNI (Ente Italiano di UNIficazione, Italian expression of ISO) during 1998-2000, and will be soon submitted to examination by the technical verification commission of UNI.
These proposals aim to provide procedures to perform and evaluate inspections on parts of hydraulic machinery (i.e. Francis, Pelton, Kaplan runners, guidevanes, etc.), thus integrating the well-known specifications CCH70-3 and the various applicable European or American norms, normally referred to by the specialists of this sector.
The two proposals emerged from the need, perceived in Italy by the main manufacturers of turbines, and the main energy suppliers, to clarify the field of the non-destructive inspections which has a great importance for hydropower, above all as regards safety in the powerplants.
New technologies have also been developed in recent years (such as, for instance, new methods for the manufacturing of Pelton runners) with a view to increasing safety and taking advantage of the new technological possibilities. These new technologies have been taken into account in these norms, which can be regarded as an updating of existing specifications.
New Italian norms to regulate the non-destructive inspections in the manufacturing and in the maintenance of parts of hydraulic machinery