No distinct correlation was found between hot and cold ovality, because the load balance changes with a movement of the tires on the rollers by thermal expansion of the kiln shell. When the rollers and/or tires abrade, the contact points change with the expansion of the shell and the load balance changes. Consequently, it is desirable to measure the hot ovality in order to understand the conditions of the kiln in operation. The linear graph generated by the hot ovality tester provides much information about the clearance between the tire and the kiln shell, load on the shell, the degree of kiln bowing, kiln alignment, and shell cracks if any. There was found a certain correlation between hot ovality and brick wear rate. A linear equation that approximated the correlation indicated that the hot ovality should be controlled below 0.425 percent for a 1-year campaign and 0.786 percent for a 6-month campaign. These limits would have to be further lowered in the areas (e.g. firing zone) where severer wear (e.g. corrosion) is expected. We believe that periodic measurement of the hot ovality helps us to assess exact kiln conditions for stable kiln operation.
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