🔍 Key Concepts

• Burner front construction and how plastic, castable, or tile fronts are normally repaired • Differences between air-setting mortars, plastics, and castable refractories • Why compatibility of material type with the original construction is important in high‑temperature areas

💭 Think About

• Ask yourself: when you "patch" something, do you usually use a material that is similar to the original or something very different? How does that idea apply to refractory linings? • Think about which choice(s) are mainly bonding agents between refractory shapes, and which are used as bulk repair material in burner fronts. • Consider what properties a burner front patch needs: resistance to flame impingement, good adhesion, and similar expansion to the surrounding material. Which option best fits those needs?

✅ Before You Answer

• Identify which listed material is primarily used as a thin joint mortar rather than a bulk patch material. • Determine which materials are designed for insulation only versus those intended to withstand direct flame and high thermal shock. • Match the form of the original burner front (plastic / castable / tile) with the most compatible refractory form from the choices.