Refractory Thermal Conductivity: Check Units and Temperature
A conductivity figure is useful only with its units, test temperature, and the lining thickness it will represent.
Thermal conductivity describes how readily heat passes through a material under stated conditions. A single figure can be misleading when two sheets use different units or test temperatures. Conductivity usually changes with temperature, so compare values over the range relevant to the lining.
Put every number on the same basis
Record whether the value is in W/m·K or another unit and whether it is measured at a mean temperature or reported for a particular test point. Do not strip the temperature from a comparison table. If several values are given, a design calculation may need more than one.
Consider the complete wall
Heat loss depends on thickness and all layers, including dense hot face, insulation, joints, and steel shell conditions. A lower conductivity material does not automatically make the best hot face if it lacks the needed strength or chemical resistance. Use the measured operating profile and the approved lining design when estimating shell temperature.
Royal's insulating castables list conductivity alongside density and strength so the trade-offs can be reviewed together.