Solid mold, as the name implies, the center is solid, made of iron plate. It is easy to ensure that the bending degree of the glass is consistent with that of the sphere. The disadvantage is that the production cost of the mold is high and the production cycle is long. In the process of hot bending and firing, the heat absorption of the mold increases slowly, and it is easy to cause the surface of the glass to appear pitting during the firing process.
Hollow dies are made of Angle and flat steel. The mold production is relatively simple, less material, mold in the process of hot bending fire heat, less in the middle of the glass in the process of firing with spring support, there will be no pitting products surface. The application of this kind of mold to the hot bending operation technology is high, because of the thermal hysteresis in the process of glass bending, the products are easy to bend over.
The frame model is a kind of mould between solid and hollow mold, which is relatively simple in production and low in thermal bending operation.