Ideal for Great-Perfoming Hollow and Lightweight Plastic Parts

a twin-sheet forming to manufacture plastic container
The twin-sheet forming process can yield lightweight durable plastic parts that are hollow for insulation, airflow, or structural rigidity. These resemble rotationally molded or blow-molded parts, but can have advantages such as:
  • Uniform wall thicknesses
  • Lightweight yet strong
  • Ability to combine material types, thicknesses and/or colors on each side
  • Lower tooling costs than blow molding
  • Faster turnaround and lower part cost than rotational molding

Twin-Sheet Forming Works Best If You Need…

Recognize your needs in any of the following? Twin-sheet forming could be your solution:

Hollow parts

The twin-sheet process creates a hollow part, which can allow for specific insulation, air flow, and/or rigidity needs. And compared with other options, this process can produce a lighter, more cost-effective part within a shorter amount of time.

Highly detailed cosmetic parts

Thanks to the advantages of pressure-forming used in the twin-sheet process, highly detailed—and lightweight—cosmetic parts are possible.

Lower cost tooling

Tooling costs for twin-sheet forming are lower than options like blow molding.

Quick turnaround for parts at a lower cost

We can produce plastic parts at a lower cost and a faster rate using a twin-sheet thermoforming process versus rotational molding—and at higher volumes.

Highly detailed plastic parts using pressure forming on twin-sheets of plastic
twin-sheet forming offers lower cost tooling than blow molding
highly detailed thermoformed plastic parts
Thermoformed plastic parts are extremely versatile

Difficult draw ratios

Twin-sheet forming makes it possible to obtain more difficult draw ratios than with other manufacturing options.

Flexibility with seam lines

To suit design preferences, welds and parting lines can vary in location around the perimeter of finished part.

Structural integrity

The twin-sheet process enables structural integrity to be designed into the part resulting in lightweight, rigid parts.

Durability and industry-compliance

Thermoform material is extremely versatile and can meet the industry demands and performance requirements for everything from medical devices and fitness equipment to electrical enclosures and industrial safety equipment.

Volumes in the hundreds to thousands

The twin-sheet process is ideal for moderate volumes.

Lightweight yet strong

Thermoplastic materials used for the twin-sheet process can equal or exceed the strength of metal or fiberglass and yet are lighter.

Multi-colored parts

Parts can be produced from two different-colored sheets.
Twin-sheet thermoforming for multi-colored plastic parrts

Understanding the Twin-sheet Forming Process

Twin-sheet forming is the simultaneous heating of two thermoplastic sheets and forming them between two pressure-forming tools.

First, a vacuum force is applied independently to pre-form each sheet. Once formed, the tools are quickly brought together, and compressed air is injected into the space to force the material to fuse together.

The result is a hollow plastic part that resembles rotationally molded or blow molded parts. But twin-sheet parts provide the added advantages inherent to thermoforming, like faster turnaround for strong, lightweight parts with high performance demands. See more details below.

Twin-sheet vs. blow molded and rotationally molded parts

So why twin-sheet forming? Consider this: Rotationally molded parts tend to be heavier, with thick corners but with thin walls. Twin-sheet parts, on the other hand, have more uniform wall thicknesses, and will be lighter.

And compared to blow-molded parts, twin-sheet forming allows for the use of a plug and/or the insertion of molded-in components into the hollow areas of the part—virtually impossible for blow-molded parts.

How Customers Benefit from Our Extensive Twin-Sheet Forming Experience

Profile Plastics makes a concerted effort to learn from every twin-sheet forming project we do. The crucial insights we’ve accumulated help us to continually optimize both the process and the parts themselves. This kind of knowledge benefits customers in a range of ways.
thermoformed twin-sheet plastic parts

Common applications:

  • Door panels/trays
  • Air ducts
  • Insulated cap or top
  • Engineered shock absorbers

Interested in working with us on a project?