Welding of nickel packing in nuclear power equipment

The aim of the project was to experimentally establish the optimum parameters for nickel wire welding during nuclear facility repairs. Both the WIG method and the plasma welding method proved to be applicable to obtain high-quality welded joints of nickel packings used in WWER type reactor components. The latter method appears to be somewhat more convenient, the introduced heat control and the molten pool control being easier here than in the WIG method. Of the tested welding supplies for the WIG method, UTA 200 and WIGGI 150 G type supplies gave the best results, and of the filler materials used, GRINI T-NICKEL wire exhibited the best properties. Guidelines for welder training could also be set up based on the experience gained. For instance, porosity ceased to occur in the welded joints as the welders became more and more skilled. (Z.M.). 16 figs., 4 tabs., 7 refs