Expansion joint
Joints in the refractory masonry used to absorb thermal expansion; the joints are ideally offset.
Nowadays, appropriate cords or other combustible materials such as cardboard or pieces of wood are inserted in the joint; they burn after heating up or preheating and leave a joint. The required width of the expansion joint depends on the refractory material used.
| Stone quality | Thermal expansion up to 1000 °C in % | Width of the expansion joint in mm |
| Silica | 1.2 to 1.4 | 10 to 15 |
| Magnesia | 1.3 to 1.4 | 20 |
| Forsterite | 1.1 | 20 |
| Chromium ore | 0.8 to 0.9 | 13 |
| Fireclay | 0.5 to 0.7 | 5 to 8 |
Additional references:
Lining
Basic lining
