In thermoforming, plastic sheets are heated and shaped on molds through a variety of different processes. And one of the most common ways to mold parts is through vacuum forming.Vacuum forming involves a series of specific steps:
- A material blank that has a length and width greater than the finished part is loaded into a clamp frame to be carried through the process.
- The blank in the clamp frame moves into an oven where it is heated to the forming temperature. At the forming temperature, the material is softened and pliable.
- The material is then moved from the oven to the forming station. The softened blank is sealed on the deck of the tool. In some instances, low pressure air will pre-stretch the material to enhance wall thickness uniformity on the finished part.
- A vacuum is drawn between the blank and tool to form the softened material against the tool surface. In pressure forming, while the vacuum is drawn to avoid air entrapment, positive air pressure is applied on the non-tool side of the material to force the material against the tool surface.
- An option for the process when using female tools is to use a ‘pusher’ or ‘plug assist’ on the non-tool side of the blank to control and improve material distribution in the finished part.
- The (now) formed part, while still in the clamp frame, is removed from the forming tool.
- The clamp frame releases (opens) for part removal.
- The formed part is now ready for the next step – trimming.
Vacuum forming boasts many advantages, including design flexibility, low-cost tooling, and fast turnaround, making it the perfect choice for custom plastic designs – and providing users a competitive edge.
Please contact us at our Southern California headquarters today at 714-894-5566 or [email protected] to learn more about our manufacturing solutions and how they can meet your needs.