What is pressure forming?
Pressure forming refers to the process of using air pressure on a heated plastic sheet to create a mold or part that can exhibit high degrees of detail and texture.
Using the process, the maximum pressure exerted is up to four times higher than vacuum forming.
How does pressure forming work?
First, a plastic sheet is inserted into a pressure-forming machine, so that it sits over a tool. It is then heated. Once the proper temperature is reached, up to five tons of pressurized air pushes the plastic sheet over the tool, then holds it under high pressure. An air vent removes any excess air. Once sufficiently cooled and hardened, the plastic is removed from the tool to be used as it is, as a mold, or to be further processed into a final part.
Benefits of pressure forming
Pressure forming offers manufacturers and end users a wide range of benefits. Among them:
- Aesthetics. The exteriors of pressure-formed parts or molds can be identical to those created with injection molding, meaning applications with textures, lettering, branding, text, or fine details work well with the pressure forming process.
- Part tolerances. Using a female tool results in parts that adhere exactly to its dimensions – and exhibit excellent tolerances – making pressure-formed parts a good choice for assemblies.
- Affordability. Pressure forming rivals injection molding in terms of final product, but can often be achieved more cheaply, thanks to pressure forming’s lower tooling cost.
- Speed. The pressure forming process – including design, tooling manufacturing, and prototyping – is often faster than injection molding or other manufacturing processes.
- Cost-efficacy. In addition to a relatively low tooling cost, pressure forming is a good choice for creating small- to medium-batch runs of products.
Vacuum forming vs. pressure forming
Pressure forming is similar to vacuum forming. But whereas vacuum forming uses a vacuum, the process of pressure forming applies up to five tons of pressure to a plastic sheet placed on a tool. Because pressure levels are much higher than in vacuum forming, users can leverage pressure forming to achieve higher levels of detail in the parts they create – or use thicker materials for more professional applications.