November 29th, 2017
Benefits and Applications of Vacuum Forming for Low Volume Manufacturing
Vacuum forming for short run or low volume manufacturing can be a valuable tool in making high quality plastic components. Vacuum forming is a manufacturing process whereby a thermoplastic material is heated and subsequently formed into a 3D shape. The forming occurs as typically vacuum pressure pulls or sucks the warmed plastic sheet material into or over a mold that determines the shape and size of the finished plastic part or component.
There are several key benefits associated with vacuum forming for low volume manufacturing. For example, the cost of tooling is significantly less than with other processes. In addition to this, the turnaround time is much faster. Because of cost savings and a faster turnaround time, the vacuum forming method is often preferred for R&D, prototyping, and, in some instances, long-term production. This can prove valuable both in low volume manufacturing as well as a technique used by plastic prototype suppliers for making plastic prototypes. When correctly applied, vacuum formed products can provide quality in appearance and function. The sheet material can be ordered in color and with grains and textures applied to the show side of the part. This can allow the finished vacuum formed part to appear as if it is made from much more expensive grained injection tooling.
Additional benefits associated with vacuum forming for short runs include:
- Highly detailed formed products are possible in a range of sizes
- Higher production speeds than fabricated assemblies
- Reduced equipment costs for large parts as large parts do not require high tonnage presses as would be true for injection molding
- Adaptive to the customer’s needs and can be optimized for material and appearance
- Flexible tooling design
- Visually appealing aesthetics
- Quick changes with minimal added tool change cost
- Weight savings possible for low volume manufacturers and consumers through conversion of sheet metal fabrications to
- single formed plastic components
- Available in colored, textured, and paintable plastic
- Anticorrosion spray is not required.
- Easier production that a comparable sheet metal fabrication
Products made with vacuum forming for low volume manufacturing are often used in place of complex-shaped components constructed from fabricated sheet metal. We have seen this conversion particularly in air distribution ducting and systems. Fabricated sheet metal products often require extensive operations pertaining to welding, grinding, and finishing. Likewise, when compared to other plastic forming operations such as resin transfer and fiber-reinforced plastics molding, vacuum formed parts are often more favorable due to better cosmetics and economics. This is why so many low volume manufacturers choose this option.
Products Vacuum forming for low volume manufacturing is ideal for numerous applications. Some examples include the following:
- Consumer Products
- Medical and Healthcare
- Outdoor Kiosks
There are however limitations in the vacuum forming process. For one, vacuum forming is a sheet-based process, which means that the designed product must be uniform in wall thickness throughout and formable by a single material sheet. For example, complex geometries which contain backside attachment ribs, bosses, or other features would not be compatible with vacuum forming because the geometry does not lend itself to a formed sheet design. In those cases, the additional features would have to be added by some secondary measure such as gluing or fastening the additional features which depending on the application, may or may not be practical. Similarly, vacuum forming tends to work best when applied on geometries that can be formed from a single direction of draw, without the need for side actions. Although in some cases these can be accomplished through secondary loose pieces in the tooling, it generally complicates the tooling and slows cycle times significantly. As a result, geometries with multiple side actions and those with backside geometry features or varying wall thickness areas are better candidates for injection molding or urethane casting operations rather than vacuum forming. Finally, there can also be limitations relative to the depth of draw. As the material is sucked deeper and deeper into the mold, the plastic material stretches and extends, which can thin the thickness of the formed sheet. Based on all these factors, it is important that a good feasibility analysis be performed by any prospective plastic manufacturer to ensure a proper process is selected for the product.
To gain more information about the vacuum forming or if you need low volume vacuum forming services, we invite you to contact us at Globaltech Ventures. Our personnel are experienced and have utilized vacuum forming operations for many years on a diversity of products. Likewise, GTV assembles high quality production vacuum formed interior modules for heavy vehicles on a daily basis and would be glad to discuss how this process could be applied for your projects. For assistance with the design, prototype, or manufacturing of parts or components, please call to speak with one of our experts.