METHOD OF TREATMENT OF CERAMIC ARTICLES AND DEVICE ITS FOR REALIZATION Russian patent published in 1997 - IPC

FIELD: electrothermics. SUBSTANCE: method includes laying articles, preliminary roasting, high-temperature roasting and blowing. preliminary roasting is effected in batch unit with rolling-out hearth characterized by definite sizes of working chamber and rolling-out hearth provided with metal spiral heaters and outlet branch pipe. Preliminary roasting conditions: heating to 300<$E+->10 C for 180<$E+->10 min, holding time, 120<$E+->10 min; heating to 600<$E+->10 C for 180<$E+->10 min; holding time, 120<$E+->10 min; heating to 900<$E+->10 C for 120<$E+->10 min; holding time and smooth cooling to 150<$E+->10 C for 600<$E+->15 min; at all stages, blowing with air is effected at rate of 0.2-2 cu.m/h. At high-temperature roasting, articles are smoothly moved through 12 zones of straightway device characterized by definite a sizes of working chamber and definite length of heating zones; device is provided with four outlet branch pipes and one inlet branch pipe, spiral metal heaters and water-cooled chamber. High temperature roasting conditions: heating from 170<$E+->10 C; heating temperature is raised by 170<$E+->10 C in each zone; time of heating does not exceed 78<$E+->5 min in each zone; at 400<$E+->10C, blowing with air is effected at flow rate of 0.1-1 cu. m/h followed by holding for of 120<$E+->10 min at temperature of 1200<198>C; then stage-by-stage cooling to temperature of 120<$E+->10 C is effected for 900<$E+->20 min in device and final cooling to temperature of 20<$E+->10 C is effected beyond device. EFFECT: enhanced efficiency. 3 cl, 2 dwg