High-alumina brick lining is divided into four categories according to the size of the brick joints and the fineness of operation. The types and sizes of the brick joints are:
The fire mud in the brick joints should be full, and the brick joints in the upper and lower layers should be staggered. The following principles should be followed for the preparation of refractory mud for bricklaying.
1.1 Before bricklaying, pre-experiment and pre-laying should be carried out on various refractory muds to determine the bonding time, initial setting time, consistency and water consumption of different muds.
1.2 Use different utensils to prepare different muds and clean them in time.
1.3 The use of clean water for the preparation of different slurries, the amount of water must be accurately weighed, the blending should be uniform, and it can be used with the adjustment. The hydraulic and gas-hardened muds that have been prepared shall not be added with water, and the already-consolidated muds shall not be used.
1.4 The required mixing time should be ensured when preparing phosphate-combined mud. It must be adjusted as needed. The prepared mud must not be diluted with water at will. Due to its corrosive nature, this mud must not be in direct contact with the metal shell.
1.5 Before brick lining, the site should be thoroughly inspected and cleaned.
1.6 Before the brick lining is built, the laying work should be done, and the size and elevation of each part of the brickwork should be checked according to the design drawings.
1.7 The basic requirements of bricklaying are: bricks are close to each other, the bricks are straight, the circles are accurate, the bricks are locked firmly, in a good position, do not sag, and the masonry should be flat and vertical. The high-alumina bricks should be built with staggered joints, the mud in the masonry brick joints should be full, the surface should be hooked, the brick joints should be horizontal and vertical, the arc surface is smooth and the masonry is dense.
1.8 Use flexible tools such as wooden hammer, rubber hammer or hard plastic hammer when laying bricks. Do not use steel hammers or cut bricks on the masonry. After the mud is hard, do not forcefully beat or correct the masonry.
Bricks should be strictly selected. Bricks of different materials and different models should be strictly separated. Bricks of the same quality and the same type should have the same length.
1.9 The thickness of the joint steel plate for dry masonry is generally 1 ~ 1.2mm, which requires smoothness, no curling, no distortion, and no burrs. The width of each board should be less than the width of the brick by about 10mm. When masonry, the steel plate should not exceed the edge of the brick, and the phenomenon of steel plate sounding and bridging should not occur. Only one steel plate is allowed in each seam. The narrow steel plate for adjustment should be used as little as possible. The cardboard used for expansion joints should be placed as designed.
2.0 When locking bricks, use flat bricks to lock and finely process, and the adjacent brick road should be staggered by 1 or 2 bricks. It is strictly forbidden to lock the bricks with castables alone, but it is possible to fix the last brick with castables.
When masonry refractory insulation lining should strive to avoid the following common problems.
1 Misalignment: That is, unevenness between layers and blocks and blocks.
2 Oblique: That is uneven in the horizontal direction.
3 Uneven gray joints: the width of gray joints varies, and can be adjusted by selecting bricks appropriately.
4 Climbing: That is, there is a regular unevenness on the surface of the wall surface, which should be controlled to be staggered within 1mm.
5 Off center: That is, the brick ring and the shell are not concentric in the arc-shaped masonry.
6 Multi-seam: That is, the upper and lower gray seams are overlapped, and only one gray seam is allowed between the two layers.
7 Through seam: It is not allowed that the inner and outer horizontal gray seams meet, exposing the shell,
8 Uneven gaps: In the arc-shaped masonry, the gray gap is small inside and outside.
9 Void: That is, the mortar is not full between the layers, bricks and the shell, and it is not allowed in the lining of the immobile equipment.
10 Rough seam: the brick seam is not smeared, and the wall is not clean.
11 Snake-bending: That is, the longitudinal seam, ring seam or horizontal seam is not straight, but wavy.
12 Masonry bulge: due to the deformation of the equipment, the relevant surface of the equipment should be leveled during the masonry. The insulation layer can be used to smooth the double-layer lining.
13 Mixing: Misuse of mud is not allowed.
14 The fire-resistant and heat-insulating composite lining of the masonry equipment shall be built in layers and sections, and mixed-layer and mixed-mortar construction is strictly prohibited. The masonry insulation lining should also be filled with grout and joints. When encountering holes and riveting and welding parts, bricks or boards should be processed, and the gaps should be filled with mud. The practice of paving arbitrarily, leaving gaps everywhere or not using mud is prohibited. In the heat insulation layer, wherever it is under anchoring bricks, behind arch bricks, around holes and in contact with expansion, high alumina bricks should be used instead.
15 Expansion joints in high-alumina brick linings must be set according to the design and must not be omitted. Negative tolerances should not appear on the width of the expansion joint. There should be no hard debris in the joint, and the joint should be filled with refractory fiber. There is generally no expansion joint in the heat insulation layer.
16 The lining of important parts and parts with complex shapes should be pre-built. For the lining with extremely complicated structure and too much brick processing volume, consider using castable lining instead.
17 Exposed metal parts left in the brick lining, including brick supporting plates, brick retaining plates, etc., should be sealed with special-shaped bricks, castables or refractory fibers, and they should not be directly exposed to hot kiln gas during use.
18 Anchoring bricks are structural bricks of masonry, which shall be retained according to the design regulations and shall not be omitted. No cracked anchor bricks shall be used around the hanging holes. The metal hooks should be laid flat and solid. Hanging holes and hooks cannot be stuck, and the gaps left can be filled with refractory fibers.
19 When masonry capping bricks, joint bricks and corner bricks, if the original bricks cannot meet the sealing requirements, the bricks should be finished with a brick cutter, and manual bricks must not be used.
20 The size of the processed brick: the capping brick should not be less than 70% of the original brick; in the flat joint brick and the curve brick, it should not be less than 1/2 of the original brick. The original brick must be used for locking. The working face of the brick is strictly prohibited from secondary processing. The processing surface of the brick should not be facing the furnace, working surface or expansion joint.