Study of Reasons for Damage of Steel 45Kh25N20S Centrifugally-Cast Tubes in Reaction-Heater Furnaces

Resumo

Factors are analyzed causing damage of reaction-heater furnace centrifugally-cast tubes (of steel 45Kh25N20S). On the basis of a loading model the stress-strained state of a tube close to annular welded joints is calculated and reasons are explained for nonfulfillment of strength conditions due to imperfection of the technology for pipe manufacture and a lack of specifications for the upper strength limit of welded joints with respect to basic metal. Recommendations are provided for preventing tube damage.