5. Construction process of mullite insulation brick
(1) The masonry sequence and masonry height of mullite insulation bricks should be determined according to the masonry structure.
(2) Mullite insulation bricks or light-weight refractory bricks should be laid by pulling threads and brick joints should be staggered.
(3) Thick mud should be used for leveling of mullite insulation brick masonry. When there is an obstruction by embedded parts or special-shaped bricks, it is advisable to use processed bricks for leveling.
(4) When laying mullite heat-insulating bricks, the horizontal joints should be laid with ash, and the vertical joints should be squeezed with ash-raising methods.
(5) It is not advisable to leave expansion joints in the mullite insulation brick masonry, but when the movable ends of other equipment and components are facing the insulation refractory brick, and the expansion value is large, the elastic refractory fiber thermal insulation materials shoudl be used to replace thermal insulation refractory bricks.
(6) When the expansion joints of refractory masonry, especially the straight expansion joints are facing the thermal insulation masonry, the mullite insulation bricks at this area must be replaced by refractory bricks. Generally, one layer of standard refractory bricks should be laid flat or erected. Just cover the expansion joint.
(7) Light-weight mullite insulation bricks should be manually squeezed for alignment. It is not suitable to strike with a mallet. For the dried insulation bricks, no percussion, collision or other vibrations are allowed.
(8) The width of the brick joints of the insulated masonry should be less than 5 mm. The mud grade and mix ratio must meet the design requirements, and the fullness of the wet-laid mullite insulation brick joints shall not be less than 80%.