Vacuum forming, commonly known as Vacuforming, is a simplified version of thermoforming , whereby a sheet of plastic is heated to a forming temperature, stretched onto or into a single-surface mold, and held against the mold by applying vacuum between the mold surface and the sheet. Vacuforming is one of the most versatile and economical processes available for manufacturing returnable packaging and many other products.
The strengths of thermoforming are as follows:
. Parts have low internal stresses therefore good physical properties to work with.
. Lead time and mold changes are relatively short and easy to perform.
. Large part don't increase costs.
Suitable materials for use in vacuum forming are conventionally thermoplastics , the most common and easiest being High Impact Polystyrene Sheeting (HIPS). This is molded around a wood, structural foam or cast/machined aluminum mold and can form to almost any shape. Vacuum forming is also appropriate for transparent materials such as acrylic.