Refractory brick will have linear change and volume change during using, the main index is linear change on reheating . It is an irreversible volume process about the linear volume change on reheating of refractory brick product, but thermal expansion is a reversible process.
Refractory bricks as the construction material of thermal equipment, often used in the high temperature and the temperature changes repeatedly. The product volume change mainly depends on the linear expansion. Therefore, even if the product shrink on reheating during using, also need to set the expansion joints, to accommodate the product linear expansion due to repeated temperature changes.
The location of the expansion joints should avoid the force parts, such as the furnace body skeleton and the cavity of the lining, to avoid affecting the overall strength of the refractory material, and the expansion joints should be uniformly set under the premise of keeping a reasonable space.