PVC foamed board, also known as Andy board and Chevron board, can be divided into two categories from product appearance, performance and production process: ① skinned foamed board, which is produced by seluca principle, has a layer of hard skin on the surface, smooth and flat, high hardness, good mechanical properties, high product precision and small thickness error, and has strict requirements for mold, formula, materials and production process; ② Free foaming board, the product surface is loose without crust, showing fine concave convex pitted surface, which is conducive to printing, spraying and veneering. It can be produced by using ordinary foaming mold, and the process is relatively easy to control.

The process flow of PVC foam board is to accurately weigh the raw materials and feed them in order according to the process requirements. The addition time of foaming agent is determined according to the type of foaming agent used to reach the kneading end point. When the material temperature reaches about 125 ℃, quickly put the material into the cold stirring pot for cooling and reduce the temperature to about 50 ℃, so as to prevent caking and premature decomposition of foaming agent from affecting the foaming ratio and increasing the product density.