Experimental Study of the Method for Resistance Heat Treatment of Tubes for Steam Generator

摘要

The main reason for appearance and development of corrosion damage of the nuclear power plant (NPP) steam generator heat exchanger pipes is the process of stress corrosion cracking of metal under the influence of the residual tensile stresses.The method for heat treatment and straightening of the heat exchanger pipes using distension is proposed. The approbation of the process in a production environment is carried out. The construction and operation of the experimental installation are described. The experimental results show that the proposed method provides mechanical properties, grain size and resistance to intergranular corrosion of metal pipes in accordance with the requirements of Standard Specification 14-3P-197-2001 (Seamless pipe of corrosion-resistant steels with improved surface condition). In pipes, heat-treated by the proposed method, the level of residual tensile stresses and the curvature are one order less than in the tubes, heat treated by the technology which is usually used.