The mould is made of high carbon chromium bearing steel, GCr15, with strong hardness. 

A complete mold mainly consists of four parts: mandrel, upper cover, bottom plate and outer ring. Among them, the outer ring is also divided into strip and strip. The steel belt is located in the middle of the outer ring to protect the outer ring during use. 

If the outer ring is worn, it only needs to replace the outer ring, instead of replacing the whole outer ring, thus reducing the cost. According to the different products produced, the bottom plate of the mold is divided into hanging glue and not hanging glue. Moulds can be selected according to customer requirements