Construction of Furnace Refractory Line: Bottom and Wall

1. Before constructing the bottom, first make the base level. If necessary, process the bricks of the lowest layer to make the base level. Before constructing the inverted arch bottom, identify the curved surface with a template. The slope bottom should be constructed by measuring and setting out. 

2. The construction sequence of the bottom and wall should meet the design requirement. The bottom that requires frequent repair should be constructed into live bottom. 

3. When constructing the bottom, the upper layer or the upper two layers should be laid laterally. The smooth surface of the top layer should be perpendicular to the direction of air flow or slags. If necessary, the top layer can be constructed in a herringbone shape and the lower layers can be laid flatly with joints staggered with each other. The levelness and height should be checked every time a layer is finished to ensure the final top elevation. 

4. For the slope bottom constructed with horizontal layers, the triangle part, formed with set-back models of the lower working layer, can be made level with corresponding refractory castables, ramming masses or plastic materials. 

5. When constructing the ring furnace, stepping hearth furnace and trolley furnace, joints between the removable bottom and other parts should be reserved according to the design requirement. The edge bricks of the bottom should be laid laterally to ensure its strength. 

6. In the walking beam furnace, the insulation board of the bottom should be laid in the dry state and the joints should be staggered. When laying the second layer of insulation bricks, a square pit should be reserved for casting insulation castables at the bottom of water beam column. No adhesive is applied between the two layers and joints should be staggered each other. Then lay two layers of refractory bricks. A square hole should be reserved around the column for casting dense castables. Expansion joints should be reserved and filled with ceramic fiber. Then cast dense castables. Thin high alumina bricks are laid over expansion joints. Build a low wall in the bottom opening after wrapping the column. 

7. The inverted arch bottom should be built from the center to the sides. The long side of the top layer bricks of the non-curved bottom and channel bottom should be perpendicular or at an angle to the direction of charge, metal, slag or gas flow. 

8. In order to maintain the level of the brick layer, the straight section of the walls should be built according to the benchmark and rope along the edges of the masonry. The higher the more difficult to keep the overall straightness. Thus, each layer of the masonry must be straight. The masonry of the furnace wall should be vertical and horizontal. 

9. The wall of the round furnaces should be built based on the centerline. When the vertical error and diameter error of the center line can meet the requirements of the inner shape of furnaces, the wall can be built with the shell as the guide surface. 

10. When the center line and diameter error can meet the requirements of the inner shape of furnaces, horizontal circular masonry should be built with the shell as the guide surface.

11. The arc wall should be built according to the template. During the constructing, always check it with the template. 

12. For the furnace wall hooking brick or hanging brick, the force surface should be close to the pendant and a certain room should be reserved between the pendant and other surfaces. 

13. The pull rod and pull hook in the furnace wall should meet the following requriements: 1)the pull rod should be straight and its curvature per meter length should not exceed 3mm; 2)the length of the pull rod should be appropriate; 3)the pull rod should be disconnected at longitudinal expansion joints; 4)the pull kook should insert the brick straightly. 

14. The pull hook of the insulation bricks should be located in the middle of insulating bricks. 

15. The upper surface of the wall under the arch bricks should be made level according to the design elevation. The surface should be smooth. The distance between the arch brick and the center line should meet the design dimensions.