Which type of tamping mix is most suitable for repairing cracks in refractory?

The choice of FC-25 fiberfax as the most suitable tamping mix for repairing cracks in refractory is based on its specific properties that enhance the repair process. FC-25 fiberfax typically contains reinforcing fibers that improve its strength and thermal resistance when compared to other mixes. These fibers help bridge any cracks or gaps during thermal cycling, which is particularly important in environments where temperature fluctuations can cause further damage to the refractory materials.

Additionally, fiberfax has a composition that ensures better adhesion to existing refractory surfaces, making it ideal for repairs. The mix is designed to withstand high-temperature conditions and is formulated to maintain its integrity under stress, making it less likely to crack or degrade over time.

In contrast, other potential options like standard mortars may not possess the necessary thermal properties or flexibility required for effective repairs in high-temperature situations. Resin-bonded refractories could also be a valid repair method, but they typically serve different applications and may not provide the desired durability in certain situations. Thus, FC-25 fiberfax stands out for its specific features tailored for the challenging conditions present in refractory repair work.