IMPROVING THE OUTPUT QUALITY OF STEAM TURBINE WELDED ROTORS FOR NUCLEAR POWER PLANTS

mproving the reliability of welded rotors (under conditions of increasing operating loads) is an urgent task in nuclear power engineering. The solution to this problem was achieved by automatic welding of rotors in optimized welding mode parameters using new welding materials. It resulted in obtaining welded rotors with improved quality characteristics of their output structure and without defects, such as pores and non-metallic inclusions. The austenite grains in the structure of the welded joints became much smaller in size. The new austenite decomposition products in the area of incomplete recrystallization of the heat-affected zone were sorbite and troostite, rather than pearlite, which was obtained during the standard automatic welding process. Thus, automatic welding of 25Х2НМФА steel rotors in optimized modes and the use of new welding materials ensured the production of the welded joints with improved quality characteristics of their output structure, which increased the reliability of rotor operation