Factors affecting the reliability of water turbines were discussed in the first part of the report. One of them is the resistance of flow parts to cavitational erosion. It was mentioned that the specific situation (water turbines are not built in this country) requires, among others, that modern methods should be applied for repairing the cavitational damages with the aid of materials resistant to cavitation erosion in order to iincrease the reliability and lifetime of the machines in use.

Nert, the proper arrangement of functions concerned with the regeneration of the damaged components was presented. The order and scope of necessary works at the respective stages of repairs were specified. More detailed discussion of various methods of surface regeneration, such as putting on anti-cavitational coats with the aid of electric arc, covering the components with alloy steel sheet, flame-coating with metal powders as well as covering with plastics, was given.