Masonry of Catenary Vault of Hot Blast Furnace:
（1） Before masonry of catenary arch top, the height of plastering layer should be determined first, which can be determined according to the design elevation of the uppermost refractory brick of the column masonry section.
(2) Mark a number of horizontal lines at certain intervals on the spray coating layer of the furnace shell as the height line of the masonry layer to control its levelness.
(3) When building masonry, use the radius gauge to check and control the masonry radius of the masonry at any time.
(4) When building arc-shaped refractory bricks, the hook fixing method is used for masonry, that is, the upper refractory bricks are fixed on the lower refractory bricks with the long arms of the hooks.
In the front section of masonry, one hook should be used for every 4 to 5 bricks. As the slope becomes larger, the number of hooks should be gradually increased. When the last few rings of refractory bricks, one hook should be used for each brick. The hook can be removed only after there is a back door.
(5) During the masonry process, the rotating template can be used to control the size of the arc-shaped masonry, and the brick layer line is marked on the rotating sample surface to control the height of the refractory bricks.
(6) Check the horizontal radius and elevation of the masonry layer by layer, and confirm that it meets the design and construction requirements
(7) Strictly check the quality and dimensions of the refractory bricks, and determine the specifications of the processed bricks through pre-laying inspection joints to ensure that the deviation of the arc-shaped section of the masonry is within the allowable range. The height of the masonry should be checked at any time during masonry. The slope should be adjusted in time.
(8) Lightweight refractory bricks (including thermal insulation materials) for the outer environment-friendly temperature layer of the arc section should be simultaneously built with refractory bricks for the inner ring.
(9) The temperature-measuring hole section of the vault is trumpet-shaped. Before masonry, a small arch tire and a central wheel rod should be installed at the lower part to assist in the rounding. The temperature measuring hole bricks generally use combined bricks or processed bricks. When using processed bricks, they should be pre-built and assembled in place before formal masonry.
- Masonry of external combustion vault and connecting pipe of hot blast stove:
(1) The vaults of the external combustion regenerator and the combustion chamber are hemispherical, with a connecting pipe in the middle. The lower half of the connecting pipe is connected with the straight section under the vault, and the upper half is connected with the vault. The centerline of the nozzle assembly brick and the centerline of the connecting pipe form an angle of about 10°.
(2) The vault and the connecting pipe should be constructed synchronously. Prior to this, the radius wheel rod, the arc model rotary wheel rod, and the arc model rotary wheel rod should be installed in sequence according to the construction sequence.
(3) The vault line is laid out, and the center line is drawn according to the center of the furnace roof flange, and the center point of the vault masonry is used as the masonry reference of the furnace roof refractory bricks.
(4) When building the furnace trough of the straight tube section under the vault, use the radius wheel rod to strictly control the inner diameter of the masonry, check the top level and levelness and ensure that it is consistent with the bottom elevation of the first layer of composite bricks under the connecting pipe.
(5) The connecting pipe combination bricks include inner ring bricks, middle ring bricks and outer ring petal bricks. The masonry of the lower semicircle of the connecting pipe should be carried out in order from the inside to the outside, and the inner radius of the connecting pipe should be controlled and adjusted many times to ensure the quality of the masonry. During masonry construction, the model wheel bar and the rotary wheel bar are used to check and control the inclination angle of the first ring of the upper and lower connecting pipes.
(6) Refractory bricks for spherical vault roofs should be built ring by ring. The vault bricks should be prefabricated and placed dry and stitched together. The extension direction of the brick joints should be consistent with the radius of the vault.
(7) The spherical vault also uses the metal hook fixing method for masonry, and the last few rings of refractory bricks can be used for the auxiliary masonry construction of the plug-in arch.