PURPOSE: To efficiently and stably allow the execution of adequate annealing by adjusting annealing conditions during the passage of the dummy steel strip interposed between preceding and succeeding steel strips and controlling the quantity of the heat to be charged at the time of a transfer according to the number of the passage times of the dummy steel strips.
CONSTITUTION: The dummy steel strip B is interposed between the preceding steel strip A and succeeding steel strip C of the different annealing conditions and the annealing of the steel strip A then the steel strip C is executed by passing the steel strips in a continuous annealing furnace 1. The furnace temp. detected by a thermocouple 2 during the passage of the above-mentioned dummy steel strip B is adjusted to the annealing conditions of the succeeding steel strip C by changing the amt. of the combustion gas to be charged via a controller 3. The quantity of the heat to be charged at the time of the annealing of the succeeding steel trip C is controlled according to the number of the passage times of the dummy steel strip B in the above-mentioned method for controlling the temp. of the continuous annealing furnace 1. The change ΔQ (Nm3/hour) of the amt. of the gas to be charged at the time of the transfer is preferably executed by equation ΔQ=K1(N)×(F2-F1) (where K1 (N): the coefft. determined by the number of the passage times of the dummy steel strip B, F2: the product of the thickness, width and line speed of the succeeding steel strip C, F1: the product of the thickness, width and line speed of the dummy steel strip B).
| WO/2016/055230 | METHOD FOR PRODUCING HARDENED STEEL COMPONENTS |
SATO TOSHIYA
MURABAYASHI MINORU
SATO TAKASHI
| JPS61117229A | 1986-06-04 | |||
| JPS6070128A | 1985-04-20 | |||
| JPS6289820A | 1987-04-24 |