The masonry requirements, regulations and precautions of metallurgical roasting furnace body shall be compiled and issued by the refractory brick manufacturer.
- Inspection, acceptance and setting out of furnace shell before masonry:
After the installation of the furnace shell, mark the center line of the furnace body first, then recheck the ovality of the furnace shell and the elevation of each part, then mark the center line of each hole of the furnace body and the masonry elevation of the furnace wall, and set out for masonry.
- Construction of refractory castable for distribution plate surface:
The refractory castable for the distribution board shall be poured after the masonry of the furnace shell and vault is completed, the embedded air nozzle is installed and checked to be qualified, the air nozzle is sealed and the construction area is cleaned. Light castable shall be poured first, and then heavy castable.
The castable shall be mixed with a forced mixer, the amount of various materials shall be mixed according to the construction instructions, and evenly mixed in the mixer, then the specified amount of water shall be added and fully mixed for 2 ~ 3 minutes.
The mixed refractory castable shall be used up within 30 minutes, and the castable in initial setting state cannot be used any more. During the pouring process, the plug-in vibrator shall be used for tamping. The pouring material on the fluidized bed surface shall be poured at one time, and no construction joint shall be reserved. The surface of castable shall be flat and leveled at any time during pouring. 24 hours after the construction of the castable, it shall be watered for curing. The curing time shall be at least 3 days, and the curing temperature shall be 10 ~ 25 ℃.
- Refractory brick masonry of furnace body:
(1) Masonry requirements:
In addition to some special brick types, refractory bricks need to be constructed by staggered wet masonry. The refractory mud used for masonry brick joints should be full and dense, and the size of brick joints should meet the design requirements. Wood hammer or rubber hammer should be used when leveling and adjusting the thickness of brick joints.
It is not allowed to shake or knock the masonry completed.
During masonry pointing, thick refractory slurry shall be used and filled tightly before the brick joint is solidified.
During the masonry of processed bricks, the processing surface of refractory bricks shall not face the furnace and expansion joint, and the length and width of processed bricks shall not be less than 1 / 2 and 2 / 3 of the length and width of the original bricks. Each ring of refractory bricks of the furnace wall shall be laid horizontally layer by layer. If the tenon is reserved or reworked and removed, it shall be made into a stepped inclined tenon.
(2) Preparation of refractory slurry:
The slurry used for the masonry of industrial roasting furnace can be selected according to the matching of the refractory brick materials used for the furnace wall, and can be evenly stirred by a mixer. The viscosity of the slurry shall be determined according to the actual situation on site, and the refractory slurry in the initial setting state shall not be used.
(3) Furnace wall masonry construction:
The furnace wall shall be built in sections. Before each section of furnace wall is built, the inner wall of furnace shell shall be painted with two layers of anti-corrosion coating, and then pasted with asbestos board. Then use light refractory bricks and heavy refractory bricks to start the masonry construction of furnace wall.
The masonry construction of each section of the furnace wall shall be based on the furnace shell. During the masonry of each section, if the insulation layer needs to be built, light refractory bricks shall be built first, and then heavy refractory bricks shall be built. When laying to the hole, the hole opening shall be built first, and then the surrounding furnace wall. The door closing bricks of each layer of bricks shall be evenly distributed.
(4) Masonry construction of vault brick:
1) Arch foot brick is the masonry foundation of arch crown brick, which shall be built according to the center of baking furnace, and the surface shall be kept at the same elevation. During the masonry of arch foot bricks, apply an appropriate amount of fire-resistant slurry on the masonry and make them bond well with each other.
2) After the arch foot bricks are built and inspected to be qualified, the first ring vault bricks shall be built, and the second ring vault bricks shall be built after the first ring gate bricks are built. The vault bricks shall be closely bonded with each other, and the thickness of brick joints shall be kept as uniform as possible. The door closing bricks of each ring arch top shall be evenly distributed on the furnace top, and the width of the door closing bricks shall not be less than 7 / 8 of the original bricks. The last ring vault is constructed with refractory castable.
(5) Expansion joint construction:
The expansion joints at all parts of the furnace body shall be accurately reserved according to the design drawings. The sundries shall be cleaned before filling the expansion joints. The filling materials of the expansion joints (such as refractory slurry) shall be dense and uniform, and the construction surface shall be flat.