Check whether the baking furnace and temperature control meter are normal and whether the furnace bed is flat and clean.
Carefully check the shell to be baked. The shell shall be complete and free of defects. The shell with defects must be repaired.
Clean the sprue cup edge of the shell to prevent sand from falling into the shell.
Carefully put the sprue cup of the shell into the baking furnace downward, and then the shell poured shall be installed in the furnace first, and the distance between the shell and the furnace door shall not be less than 20cm.
Ignite and heat up. When the temperature in the furnace is about 600 ℃, close the furnace door, and continue to bake until the temperature in the furnace is between 950-1100 ℃, and the heat preservation time of the shell is more than 30 minutes. The baked shell shall be white or rose.
The baking furnace shall cooperate with the melting furnace to ensure that the shell is burned well during pouring and keep high temperature. When the molten steel is qualified for pouring, open the furnace door and fork out the shell for pouring. The shell shall be forked out of the baking furnace to pouring for no more than 10 seconds. When the shell is put into the furnace or taken out, it shall be turned over and put down gently.
The maximum discharging time of each furnace shall not exceed 5 minutes.
For materials easy to oxidize, wood chips shall be added in time after pouring and covered with absolute oxygen.
Strictly control the baking temperature and time, and record that if the temperature is too high and the time is too long, the shell will burn out, resulting in the strength reduction and deformation of the shell. If the temperature is too low and the time is too short, the shell cannot be poured through, and its permeability is poor, resulting in poor pouring.
1) Check the thermometer regularly to make sure that the indicated temperature is correct.
2) It is forbidden to burn the shell twice or more.
Clean the bottom of baking furnace regularly.
When the baking furnace is ignited, no one is allowed to stand in front of the furnace.
The operator of the baking furnace must strictly abide by the process operation procedures, and the labor protection articles can only be put on duty after being dressed neatly.