The density of asbestos tile is determined by the design of asbestos tile equipment and the level of production technology. High-density asbestos tiles must be stamped and formed from semi-dry cement by high pressure (about 1250 N force). Fang Ruizheng and asbestos tile equipment use high-strength aluminum alloy molds, which can withstand strong pressure and easily make high-density asbestos tiles. High-density asbestos tiles have small internal voids, and water is not easy to penetrate. Ordinary asbestos tile equipment generally uses the production process of parallel extrusion, artificial mixing or general simple mixer, and the use of iron molds, which cannot withstand large pressure, just wipes away, so the compactness is greatly reduced. The internal voids are large and numerous, so the impermeability is poor.
 

Asbestos tile equipment

 

　　On cloudy days, rainwater will seep onto the back of the tile and drip into the roof. At the bottom of the compactness, not only the impermeability is poor, but the strength also decreases, the impermeability is poor, and it is not resistant to freezing in winter. Especially in the north, snow water seeps into the tiles during the day, freezes and expands at night, and the tiles swell and gradually peel off and destroy, and the service life of the tiles will not be long.