When refractory bricks are masonry, in order to ensure the convenience of bricklaying and use of firebricks, not only need to control the inherent quality and stability of firebricks, but also the appearance quality of fire bricks. The specific requirements are as follows.
1. Dimensional tolerance: The height tolerance is less than 1%; the thickness error of the two brick heads is less than 1mm; the width error is less than 1%, and the maximum error must not exceed 2mm.
2. Edge Loss: The hot sides and cold sides are allowed maximum two sides of damage up to 40mm long and 5mm deep.
3. Corner loss: There must be only one corner loss on both the hot and cold sides, and the sum of the loss lengths of the three edges of the corner should not exceed 50 mm. Less than 20mm is not a corner loss.
4. Cracks: The brick surfaces are allowed to have hairline microcracks; cracks parallel to the wear surface are not allowed; other cracks not longer than 40mm and not wider than 0.2mm are allowed.