Control the rate of change in the re burning line

The rate of change of re firing line refers to the residual expansion and contraction of refractory products after being reheated to a specified temperature, held for a certain period of time, and cooled to room temperature. The positive sign “+” indicates expansion, while the negative sign “-” indicates contraction. The rate of change of the re firing line is an important indicator for evaluating the quality of refractory products. The main reason for the changes in the re firing line of products with the same chemical composition is that refractory products are not fully fired due to uneven temperature or insufficient time during the firing process. In long-term use, some physical and chemical changes will continue to occur under high temperature, causing the volume of the product to expand or contract. This change has a great destructive effect on the masonry of thermal kilns, so it is necessary to strengthen the firing control in product production, so that this indicator can be controlled within the standard or even reach a smaller value.