The advantages and disadvantages of the suction molding process: Advantages: The mold cost is smaller than that of injection molding, suitable for production in smaller quantities. A mold can be made of different materials and thickness products. Disadvantages: There are restrictions on the shape of the tray, and only hemispherical trays can be produced. Product size accuracy is worse than injection molding. The classification of the molding process, according to the molds used: the main molding mold is convex mold and concave mold suction molding two kinds. Advantages of concave die: the inner surface is not in contact with the mold, so the surface is clean and suitable for the inner surface of the refrigerator, refrigerator, etc.. In addition, under the premise of guaranteeing the inner surface size, the thickness of the plate can be reduced, thus saving material and forming is also easy. Disadvantages: mold size parameters are not easy to grasp, mold internal size expansion easy, reduce difficulties, need to be equipped with bamboo frame plate supply auxiliary molding equipment.