🔍 Key Concepts

• How slag affects heat transfer between the flame, slag layer, and the refractory brick • Thermal expansion and contraction of brickwork when overheated or unevenly heated • Common types of refractory damage: shrinking, spalling/peeling, cracking, and metal anchor failure

💭 Think About

• Think about whether slag buildup tends to insulate the brick from heat or makes the brick hotter than normal • Consider what happens to refractory brick if its surface is repeatedly overheated or exposed to large temperature gradients • Ask yourself which kind of damage is most commonly associated with thermal shock or uneven expansion of the brick surface

✅ Before You Answer

• Identify whether slag buildup generally causes more heating or more cooling of the brickwork beneath it • Match each answer choice to the typical visual damage it describes (e.g., gradual size change vs. surface flaking vs. cracking vs. metal failure) • Decide which damage type is most directly linked to thermal shock from uneven heating of the refractory surface under slag