What is spalling caused by in a furnace?

Spalling in a furnace typically occurs due to sudden extreme changes of temperature. When materials such as refractories or linings are subjected to rapid temperature fluctuations, they can expand and contract at different rates. This can cause internal stresses that lead to cracking and the eventual breaking off of pieces from the surface, known as spalling.

Understanding this phenomenon is critical for maintaining the integrity of furnace linings and ensuring efficient operation. Identifying factors that contribute to temperature instability and managing heating and cooling processes can help minimize spalling and extend the life of the furnace components.

While excessive moisture, rust formation, and improper insulation can negatively impact furnace performance and longevity, they are not the primary causes of spalling related to temperature changes.