Quality requirements for refractory brick masonry for catalytic cracking furnace lining

The quality of the masonry refractory material for the catalytic cracking furnace lining is the key to determining the service life of the lining. During the construction process, the following requirements must be followed:

1. The brick joints of masonry should generally meet the following requirements:

(1) The brick gap of the nozzle brick is not more than 2mm.

(2) The dry-laid brick joint is not more than 2mm.

(3) The brick joint of refractory brick masonry is not more than 3mm.

(4) The brick joint of the insulation layer masonry is not more than 5mm.

(5) The mud should be kept clean, and water should not be arbitrarily added to the prepared mud. The mud in the brick joints must be full and even, and the other fullness should be more than 90%. The loose refractory bricks must be scraped off the old mud and rebuilt.

(6) For the brick joints of refractory brick masonry, 10 spots should be checked every 5m of masonry. The maximum brick joint thickness should not be greater than 50% of the specified brick joint thickness, and the number should not exceed 5.

The thickness of the brick joint is generally checked with a feeler gauge with a width of 15mm, and the depth of the inserted brick joint does not exceed 20mm. It is not suitable to use a feeler gauge to check the lightweight refractory brick masonry with low strength, and other measuring tools can be used to measure it.

2. The bump value of the inner surface of the brick wall should meet the following requirements

(1) Flat wall: Check with a 2m long ruler, and the gap is not more than 5mm.

(2) Round wall: the vertical direction is the same as the flat wall, and the horizontal direction is checked with a 1m long arc template, and the gap is not more than 3mm.

3. The verticality deviation of the brick wall shall not be greater than 1.5/1000 of the wall height, but the total height shall not be greater than 20mm.

4. The level deviation of the brick wall should meet the following requirements

(1) Flat wall: the length of each meter is not more than 3mm, and the total length is not more than 10mm.

(2) Round wall: the arc length per meter is not more than 3mm, and the allowable deviation of the horizontality between the corresponding two points in the diameter direction is not more than 12mm.

5. The ellipsoid degree of the cylindrical masonry is not more than 0.5% of the inner diameter of the masonry, and the maximum is not more than 20mm.

6. When the nozzle brick is divided into upper and lower layers, the deviation of its concentricity is not more than 3mm.