METHOD OF HEAT TREATMENT OF LARGE-SIZED ARTICLES Russian patent published in 2005 - IPC

FIELD: metallurgy of iron.

SUBSTANCE: method comprises heating articles up to austenitic condition, soaking, cooling, and tempering. The articles whose wall thickness does not exceed 30 mm are cooled in two stages. First, the articles are submerged into the hot water with a temperature of no less than 80°C or cold water with a temperature no more than 40°C. Second, the articles are cooled in air. The articles whose wall thickness exceeds 30 mm are cooled in three stages. First, they are submerged into hot water with a temperature no less than 80°C or cold water with a temperature of no more than 40°C. Second, short-term submerging into the cold or hot water. Third, short term submerging into the hot or cold water and/or in air.

EFFECT: reduced deformation of article faces.

2 dwg, 2 tbl