Improvement measures for cracks caused by high alumina bricks forming

November 14, 2018

Improvement measures for cracks caused by high alumina bricks forming

1) For bricks with holes, tongues, grooves or corners, you can design suitable chamfer and taper parameters. A small amount of graphite and oil mixture can be brushed on the front die to facilitate bricks to be molded and reduce cracks caused by unreasonable die structure design.

2) Reasonable design of the mold

2 mm (wide)*1 mm (deep) exhaust grooves are machined on all sides of the top and bottom plates, the distance between the exhaust grooves is 100mm, in order to facilitate the discharge of gas during the molding operation, and reduce the crack when the brick is formed. In addition to processing the venting groove on the mold, all products have vent holes on the top surface, diameter 6mm~qb15mm, distributed along the length direction 100~150mm. And processing 5mm (wide)*2mm (deep) level in the non-working surface channel to facilitate exhaust. By adopting the above improvement measures, the internal crack generated when the brick is formed and pressed is greatly reduced.

3) Reasonable installation of the forming mold

The quality inspectors of the full-time model are responsible for the on-site inspection and acceptance of the model, the brick type check and dimensional measurement of the model, and the inspection and acceptance of the model are recorded one by one. At the same time, the inspection of the mold usage should be strengthened, the wear-prone molds should be burned and welded in time to reduce the number of  the semi-finished product caused by the wear of the mold. For brick-type complex varieties, it is possible to reduce production difficulty and improve production efficiency and product quality through some measures such as model improvement.

4) When molding operation, pay attention to the uniform fabric so that the solidity of the edge and middle parts of the high-alumina bricks is basically the same, which reduces the cracks caused by the different compactness of the blank and the intermediate parts during the drying process.

5) When molding operation, press the bricks according to the operation procedure, first light and then heavy, slowly pressurize, to ensure the number of pressing times, be careful not to "short-range quick beating" and "full-range hard beating" to reduce the occurrence of internal cracks.