PURPOSE: To improve the responsiveness of a strip temperature control of a continuous annealing furnace, and to realize an energy saving by bringing directly a fuel flow rate to a feed-forward control in order to attain a fuel flow rate difference corresponding to a furnace temperature difference caused by a change of an annealing condition.
CONSTITUTION: In a method for executing a control of a strip temperature by adjusting a fuel flow rate to a radiant tube in a continuous annealing furnace, when changing an annealing condition, a furnace temperature difference to be changed and a fuel flow rate difference corresponding to said difference are derived from the present furnace temperature of the preceding plate which is passing through, and a target set furnace temperature of the following plate. Subsequently, the time when the maximum combustion is executed by the maximum fuel flow rate temporarily, or the time when the minimum combustion is executed by the minimum fuel flow rate, which can attain said fuel flow rate difference by the minimum time is derived. When a load of said following plate is higher than that of the preceding plate, the maximum combustion is executed for the time when said maximum combustion is executed, before a plate changing point of the strip passes through an inlet of a heating zone. When said load is low, the minimum combustion is executed for the time when said minimum combustion is executed, from immediately after said plate changing point has passed through the heating zone.
MORITA TAKASHI
SHIRAISHI NORIHISA
IIDA YOSHIHIRO
