Foam molding process and equipment
DATE：2022/1/24 8:43:45 / READ： / SOURCE：This station
Foam molding process and equipment
I. Overview
Compression molding of foamed plastics has many similarities with compression molding of non-foamed plastics.
Generally, the foam molding process is carried out on a hydraulic press. The plastic containing the foaming agent is directly put into the mold cavity, and then heated and pressurized to carry out the foam molding process. According to the different foaming process, the molding foam molding process can be divided into There are two categories: one is called one-step method, the plastic containing foaming agent is directly put into the mold cavity to heat and pressurize, the foaming molding process is carried out, and the foamed plastic molded products are formed at one time; the other is called two-step method. The one-step method is to pre-foam the plastic containing the foaming agent, which is called pre-foamed plastic, and then put it into the mold cavity for heating and pressure foaming molding. The two-step method is mainly used for high-foaming molding of plastics. EPS (pre-foamed PS particles) is molded and foamed, and its foaming multiple has reached 80 times.
The molding of non-foamed plastics is mostly used for molding thermosetting plastic moldings, while the molding of foamed plastics is mainly used for thermoplastics, such as PS, PE, PVC, etc., which are widely used in molding foam molding, especially PS foam. Compression molding of plastics is widely used.
Compared with the injection molding method, the equipment, molding process and operation process of the molding method are relatively simple, easy to control, less equipment investment, faster to start, and can produce high foaming, thick wall, large flat area, multi-layer bonding and other types of molds. Products, in these aspects, the molding method has outstanding advantages and has an irreplaceable position. Therefore, although its molding process is intermittent, it is still widely used. There are two types of hydraulic presses for foam molding: vertical and horizontal. The latter is easier to automate the operation process.
The molding method is one of the main molding methods for molding high-foaming plastic moldings, and is widely used in construction, packaging and daily necessities.
Author：admin