(1) The principle of low temperature slow baking and high temperature full furnace sintering should be followed. The first batch of metal charge can be added during baking and sintering, and the gap of metal charge can be minimized.
(2) After reaching the temperature increase rate of ≤100 °C/h and reaching 1000～1100 °C for 2h, continue to increase the initial charge by 90% at a heating rate of ≤100 °C/h, and then increase the temperature by ≤220 °C/h. After the speed reaches 50 °C higher than the normal tapping temperature (not higher than 1600 °C), it is kept for 1 h.
(3) Re-discharge the iron when it reaches the tapping temperature.
Furnace lining maintenance and care
(1) When a longitudinal crack occurs in the furnace wall, a slow heating method should be adopted to make the crack pass and then smelt.
(2) When there is a transverse crack in the furnace wall, the fine powder refractory material may be filled in the transverse crack according to the actual situation, and then the feed is melted.
(3) When the bottom of the furnace is eroded, it can be repaired with furnace lining, and covered with iron plate after repairing. The metal charge is melted at low power for a period of time and then melted at full power.
(4) The maintenance and maintenance of the lining is generally carried out in the case of a cold furnace. The furnace should be cooled by natural cooling or water cooling system, and water cooling is not allowed.
(5) After the smelting is finished, the molten iron is cleaned. In order to prevent cracks on the furnace wall, asbestos sheets should be added to the furnace mouth for heat preservation.
(6) If the furnace is shut down for a long time, it should be slowly heated and melted at the next opening, so that the small cracks in the lining can be self-healed.
