Refractoriness Under Load

The temperature range in which the softening of refractory products occurs is not identical with the melting range of the pure raw material; therefore it must be reliably determined. Refractoriness under load (RUL) is a measure of the deformation behaviour of refractory ceramic products subjected to a constant load and increasing temperature. The RUL is of great importance to check the suitability of refractory products for high-temperature applications; it gives an indication of the temperature at which the bricks will collapse, in service conditions with similar load.

The EN ISO 1893 Standard was issued in 2008 and is basically a revision of the EN 993-8 issued in 1997 which was based on the PRE/R19 elaborated in 1972.