Thermoforming can use one of two processes vacuum forming or pressure forming.
Pressure forming plastic.
To start we add a vessel on the opposite side of the sheet from the mold.
Pressure forming plastic produces tight crisp features.
Vacuum pressure forming.
Pressure thermoforming is a plastic manufacturing process in which compressed air is used to push the back of the plastic sheet against the mold.
Pressure forming can produce single wall parts.
Pressure forming uses both vacuum and air pressure to push the soft heated plastic more tightly against the mold giving the part sharp detail.
Plastic pressure forming is an excellent alternative to injection molding or structural foam molding in many applications especially in runs of moderate volumes.
Each has its own advantages and this table will help you decide which plastic forming machine might be right for you.
Pressure forming produces parts that have crisper detail and sharper features than conventional vacuum formed parts.
This produces three dimensional parts with features and aesthetics such as detailed surface finishes and textures that rival more expensive processes.
Pressure forming can use more than triple the amount of air pressure than vacuum forming allowing the heated plastic to better adhere to the mold in the thermoforming machine.