During the vacuum forming process, a sheet of heated plastic material is placed over a male or female mold. The meld then moves towards the sheet and presses against It to create a seal. Next, the application of a vacuum draws out the air between the mold and the sheet so that the plastic conforms to the mold exactly. Thls ls accomplished through venting holes In the mold that are joined to vacuum lines. The mold also has a water cooling system integrated into it that brings the temperature of the plastic to the set temperature needed. When the curing temperature is reached and the piece is formed, air blows back into the mold and separates the new part from the mold.
Vacuum forming produces plastic parts for various industries, such as the food, cosmetic, medical, electronics, entertainment, household products, toys, athletic equipment, appliance, automotive, office supplies and clothing industries. One of the most important industries that thermoforming serves, however, is packaging. Products like blister packs, inserts, trays and clamshells are used to house other products and are Important for both preservation of the items they hold and the aesthetic designs they can provide. Consumer product manufacturers often use vacuum formlng to produce plastlc trays and glasses.
The greatest advantage to vacuum forming is that it involves less parts and tooling than injection molding, and therefore is more cost-effective. It is an economical choice that can be used for small and medium production runs, with low cost tool modifications. There is great design flexibility available, from a variety of prototypes to custom made designs that can be used to cover almost any product. Most manufacturers also offer a wide variety of trim and other decoration options that can prove quite a visual advantage. Time of production is generally short, which frees up time to do more detail-oriented aspect of production. Sharp, precise detail is available for many products, which makes vacuum formed plastics an attractive alternative to other molding processes.