1、 Quality requirements for refractory brick masonry of hot blast stove:
- Allowable horizontal and vertical deviation:
(1) The allowable deviation in the horizontal direction of furnace wall is 8mm;
(2) The allowable deviation in the horizontal direction of furnace bottom is 8mm;
(3) The allowable vertical deviation per meter height is 3mm / M;
(4) The allowable vertical deviation of the full height of the furnace wall is 10mm;
(5) The allowable deviation of foundation brick pier height is 3mm / M;
(6) The allowable deviation of the full height of the foundation brick pier is 10mm.
- Allowable deviation of surface flatness of refractory brick masonry:
(1) The allowable deviation of furnace wall surface flatness is 5mm;
(2) The allowable deviation of surface flatness under arch foot brick and furnace wall is 5mm;
(3) The allowable deviation of furnace bottom surface flatness is 5mm.
- Allowable deviation of refractory brick masonry size:
(1) Rectangular furnace:
1) The allowable deviation of dimension in the direction of length and width is ± 10mm;
2) The allowable deviation of diagonal length direction dimension is ± 15mm.
(2) Vault:
1) The allowable deviation of span is ± 10mm;
2) The allowable deviation of arch foot height is ± 10mm.
(3) The allowable deviation of various hole centers is ± 3mm;
(4) The allowable deviation of main dimensions of outline is ± 10mm.
- Allowable deviation of refractory brick joint thickness:
(1) The allowable thickness deviation of square refractory brick masonry shall not be greater than 3mm;
(2) The allowable deviation of circular refractory brick masonry thickness shall not be greater than 2mm;
(3) The allowable deviation of thickness and dimension of ordinary brick masonry is 8 ~ 10mm.
2、 The quality standard of refractory brick masonry of hot blast stove is as follows:
- The physical and chemical indexes, specifications and dimensions of all heavy dense refractory bricks and light insulating refractory bricks used for masonry shall meet the design and construction requirements.
- the refractory bricks that are not exposed to moisture by human contact with water must be dried before they can be put into use;
- The refractory bricks shall be built at staggered peak, and no through joint is allowed;
- The expansion joint of refractory brick shall be densely filled with refractory slurry, and the fullness of refractory slurry shall not be less than 90%. When several refractory bricks are laid, powder shall be used for full filling;
- Strictly select bricks. The brick surface with missing corners and edges, cutting and chiseling of processed bricks shall not be directly laid to the furnace, the parts in contact with flame and furnace, load-bearing parts and the inner surface of expansion joint;
- For the inspection of the reserved expansion joint size of refractory brick, 10 places shall be inspected with feeler gauge on the surface of every 5 square meters. Compared with the specified expansion joint size, there shall be no more than 5 places exceeding half;
- When there is refractory brick masonry between arch foot brick and arch foot beam, the masonry refractory brick shall be closely bonded; When there is no masonry between, the arch foot brick shall be built close to the arch foot beam;
- When filling the expansion joint, the impurities or falling refractory mud in it shall be removed first;
- The expanded perlite shall be filled lightly;
- For the furnace body without steel plate shell protection, the outer surface of masonry shall be pointed;
- In winter, the temperature of refractory brick construction area shall not be lower than 5 ℃, the temperature of refractory slurry shall not be lower than 5 ℃, and the masonry mortar of ordinary brick shall not be lower than 10 ℃;
- After the masonry is completed and before it is delivered for use, the furnace drying operation shall be carried out in strict accordance with the temperature rise curve of the construction design.