The so-called empty furnace heating time refers to the time required for the color coated sheet curing furnace to heat from room temperature to process setting temperature when the steel strip is not running.
The temprature rise time of the empty furnace is affected by many factors, including the following main factors:
(1) The furnace temperature set by the furnace. The higher the furnace temperature setting, the longer the empty furnace heating time,
and the closer to the set temperature, the slower the furnace heating speed.
(2) The heat preservation performance of the furnace. The better the heat preservation performance of the furnace, the shorter the heating time of the empty furnace, and
(3) Heating capacity of furnace. The greater the heating capacity of the furnace, the shorter the heating time of the empty furnace, and vice versa.
(4) The amount of exhaust and fresh air in the furnace. The larger the exhaust
and fresh air volume of the furnace, the longer the heating time of the empty furnace. In the heating stage of the solidification furnace, after washing operation, there is no solvent and explosion danger. Therefore, under the premise of ensuring that
the heat exchanger of the incinerator is not burned out, the amount of fresh air and exhaust gas can be reduced appropriately to reduce the heat load of the solidification furnace and shorten the heating time of the empty furnace.
(5) It is related
to the heating mode of the furnace. For direct heating solidification furnaces, the heating time of empty furnaces is shorter, generally within 1-2 hours, because each zone has its own heating system. For indirectly heated solidification furnaces, because
the furnace temperature in each area is heated by hot air generated by incinerator, and the increase of hot air temperature takes a certain time, the heating time of empty furnace is longer, generally about 2-4 hours.