Basic flux-cored wire for welding heat resistant 1.25% Cr - 0.5 % Mo steels. Self-sustaining slag allows vertical up positional welding. Welds retain excellent mechanical properties after long exposure to temperatures up to 500°C. Designed for applications in oil refiners, oil and gas industry, chemical industry, ammonia synthesis processes and thermal power plants for heat exchangers, boilers, pipes and pressure vessels with operating temperatures up to about 550°C. To be used under gas shielding of Ar+CO2 mix.