Twin Sheet Forming

Twin Sheet Forming Process Profile Plastics

Twin-Sheet Forming is the simultaneous heating of two thermoplastic sheets and forming them between two Pressure Forming tools. First, vacuum 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. This results in the manufacturing of plastic parts that are hollow, and resemble rotationally molded or blow molded parts. Only better! Rotationally molded parts tend to be heavier and have thick corners but with thin walls, whereas Twin-Sheet parts have more uniform wall thicknesses, and will be lighter. Similarly, compared to Blow Molded parts, Twin-Sheet forming allows for the utilization of plugs, and/or the insertion of molded-in components into the hollow areas of the parts. This is virtually impossible for Blow Molded parts.

Advantages of Twin-Sheet Forming:

  • All thermoplastics available in extruded sheet form can be Twin-Sheet formed!

  • Parts can be produced from two different color sheets.

  • Two sheets can have different starting gauges.

  • Structural integrity can be designed into the part resulting in lightweight, rigid parts.

  • The weld or parting line can vary in location around the perimeter of the finished part to suit your design.

  • Tooling costs are lower than blow molding.

  • Parts can be produced at a faster rate, higher volumes, and at lower cost than rotational molding.

  • Parts can be foam filled after forming.