FIELD: metallurgy.
SUBSTANCE: group of inventions relates to a method for heating a steel sheet and to a continuous annealing installation. The method for heating a steel sheet in a continuous annealing unit containing a direct heating zone, a holding zone and a cooling zone, in which a direct intermediate holding zone is located between the heating zone and the holding zone, includes heating the steel sheet in the heating zone so that the temperature of the steel sheet on the exit side of the heating zone reaches a temperature that is lower than the set cure temperature by an amount of ∆T, while the furnace temperature in the intermediate holding zone is set equal to the set holding temperature of the steel sheet, moreover, the steel sheet is heated in such a way that the temperature of the steel sheet reaches the set holding temperature in the second half of the intermediate holding zone. In this case, the value of ∆T is no less than the range of values of the deviation of the temperature of the steel sheet when regulating the temperature of the steel sheet in the heating zone by means of feedback and is not more than half of the heating capacity of the intermediate holding zone for heating the steel sheet.
EFFECT: provided is an increase in the accuracy of temperature control of heat treatment to improve and stabilize the quality of products.
4 cl, 6 dwg
