Sintering process of intermediate frequency furnace lining
The working life and installation of the intermediate frequency furnace lining are generally directly related to the furnace operators. If the installation is in place, the operation is in full accordance with the rules, the perfect effect of lining can be achieved.
The sintering process of the intermediate frequency furnace lining is divided into several steps:
1. Natural drying
After the crucible is completed, it needs to be placed for 24 hours to promote its natural drying. This will make the water of the crucible to be fully and evenly dispersed, thus avoiding cracks caused by excessive raw moisture during the subsequent baking process.
Firstly, wood should be burned and baked for about 2 hours to 3 hours, after baking the furnace charge should be loaded, and temperature in the furnace should be raised from 80℃ to 120℃ per hour by power transmission, until the temperature reaches heat at 700℃ and then keep warm for another 1 to 2 hours. In the first stage, it is necessary to remove the moisture from the burden thoroughly.
In the semi-sintering stage, the heating rate should be appropriately slowed, and the heating rate should be about 70℃ to 90℃ until the temperature is raised to 1100℃. At this time the residual carbonic acid will decompose and the magnesium carbonate will decompose into magnesium oxide and carbon dioxide, and calcium carbonate is also decomposed into calcium oxide and carbon dioxide, and after 5 hours, the temperature is raised at a rate of 100℃ to 130℃ per hour until the temperature reaches 1300℃, so that the furnace lining forms a semi-sintered state.
At this stage, the cable-like charge should be fully melted until the melt fills the furnace cavity. After the thawing, the temperature should be continued to 1600℃ and kept for about 30 minutes. The coarse glaze residue is cleaned up and a thin layer of glaze slag should be maintained. The continuous melting of 3 to 5 furnaces can obtain a more perfect lining with a three-layer structure of a dry layer, a semi-sintered layer and a sintered layer.