Vacuum forming (plastic uptake) is a kind of hot forming plastic processing technology. Its principle is that heating the flat plastic sheet and make it soft and then adsorption on the surface of the mold with vacuum, molding after cooling. Although Vacuum Forming technology is a little strange to many mould engineers, products made with this technology are everywhere, which are widely used in electronics, electrical appliance, food, hardware, cosmetics, toy, daily necessities, medicine, health care products, automobile, stationery, stationery and other industries. The picture shown below is the plastic products vacuum formed.
There are many methods of vacuum forming, including die vacuum forming, punch vacuum forming, punch vacuum forming, bubble vacuum forming, auxiliary punch vacuum forming and vacuum forming with gas buffer device, which all involve the following steps: preheating – shaping – finishing:
Step1：heat and soft thin plastic sheet
Step 2：The internal air is drawn out through the air holes of the male mold, and the prototype of the softening plastic sheet is adsorbed on the surface of the male mold under the pressure of air, and then it is cooled and solidified before trimming.
It is worth noting that the forming precision of vacuum forming parts is mainly dependent on the influence of molding temperature, mold temperature and draft, and the effective contact pressure between the hot parts and the mold. The advantages of vacuum are material saving, lightweight, convenient transportation and good sealing performance. Since the vacuum forming process does not touch any mold surface, the surface gloss of the parts is high without defects. Vacuum forming is one of the most widely used thermal forming methods.