- The masonry sequence is from kiln head to kiln tail (from low end to high end), and the expansion brick joint is reserved according to the transverse ring masonry method.
- The construction shall be started from the bottom of the rotary kiln, and the masonry shall be carried out evenly on both sides along the circumferential direction. When the masonry reaches more than half a circle of 3 ~ 4 bricks (1 ~ 2 layers in the horizontal diameter direction), set up a brick masonry machine or support the top bar. The masonry shall be carried out in sections. The length direction of each section of the supporting ejector rod shall be 4 ~ 8m, while the length direction of each section of the bricklaying machine can reach more than 10m. During the masonry of supporting top bar, the next one can be carried out after the masonry of refractory brick of one material specification is completed.
- Masonry requirements:
The magnesia brick masonry shall be close to the cylinder, the brick joint shall be reserved tightly and straightly, the intersection shall be accurate, the lock brick shall be stable and firm, and there shall be no dislocation, distortion, sagging and void, etc.
- Allowable deviation:
(1) During ring masonry, the allowable deviation of circumferential joint shall not exceed 2mm / M;
(2) The allowable deviation of the whole ring length shall not exceed 6mm;
(3) The allowable deviation of distortion shall not exceed 3mm / M;
(4) The allowable deviation within the whole length of the same masonry section shall not exceed 15mm;
(5) The fullness of the refractory slurry at the masonry brick joint shall be greater than 90%, the gap between the inner wall of the cylinder and the refractory brick shall not exceed 3mm, the refractory slurry shall be densely filled and the fullness shall be greater than 95%, and the mortar joint gap between the refractory bricks shall be less than 2mm.
- Lock brick requirements:
(1) Lock bricks from the last 5 ~ 6 bricks in each ring. Try to use the original bricks of supporting lock bricks, and the thin lock bricks shall not be used continuously. The lock bricks of adjacent rings shall be staggered by 1 ~ 2 refractory bricks.
(2) When the last lock brick of each ring cannot complete the lock brick operation, the processed brick can be used. It is required that the thickness of the processed brick should be greater than 2 / 3 of the original brick. The last lock brick in the whole kiln or a section shall be finely processed, and the last three lock bricks shall be pre processed. Under the condition of wedge tightening, the upper and lower openings of the last lock brick shall be flush and wide.
(3) The mortar joint of the last 1 ~ 2 bricks can be locked without refractory mud, and it is not allowed to lock bricks with castable or refractory mud alone.
- Requirements for wedging steel plate into lock opening:
(1) After each ring (section) is built, wedge steel plates shall be used at and around the lock bricks for fastening. The surface of the iron plate shall be flat without curling, distortion and burr.
(2) At most one steel plate can be wedged into the same brick joint, which shall be used at intervals without bridging, sounding, etc.
(3) Try to use less or no steel plates, and it is forbidden to use narrow steel plates.
- Expansion joint:
2mm thick paperboard shall be reserved in the axial direction as the axial expansion joint. During masonry, the side of refractory brick with paperboard shall be on the same side.
- Brick retaining ring special-shaped refractory brick masonry:
The brick retaining ring shall be perpendicular to the central line of the kiln body, and the allowable deflection shall not exceed 1.5mm. When building special-shaped refractory bricks at the brick retaining ring, the processed bricks of corresponding size can be used according to the brick retaining ring structure.
- Construction of castable in kiln:
(1) Support the pouring formwork stably and ensure that the formwork has sufficient strength and rigidity, and there will be no deformation, displacement, slurry leakage, etc. during the construction process.
(2) The amount of water or solvent added to the castable shall be added in strict accordance with the use and construction requirements. On the premise of ensuring the construction performance of the castable, the amount of water or solvent shall be used as little as possible.
(3) The vibrator shall be used for curing while pouring according to the general pouring process, and the vibrator shall be used for curing while pouring.
(4) The construction area of the castable lining in the rotary kiln is generally at the front and rear kiln mouth. The pouring shall start from the lower half circle. After the castable reaches a certain strength (generally 4h), rotate the kiln body and then erect the formwork for the castable construction. The joint of each pouring shall be reserved with expansion joints, which can be tightly filled with slag cotton.
(5) The formwork can be removed only after the curing of castable lining is completed and meets the formwork removal requirements.