Make · process

Thermoforming

A heated sheet drawn over a mould

A plastic sheet is heated until soft, then pulled over or into a mould by vacuum or pressure — the fast, low-tooling way to make trays, packaging and large thin shells. Because the tool is single-sided, it is cheap and quick to change.

Low–high
Volume
Low
Tooling
Seconds–minutes
Cycle
Loose
Tolerance
How it works
  1. 1
    Heat a thermoplastic sheet to its forming temperature.
  2. 2
    Drape it over or into a single-sided mould.
  3. 3
    Pull it to shape with vacuum, and sometimes air pressure.
  4. 4
    Cool it, then trim the part out of the sheet.
Strengths & limits
Strengths
  • Low tooling cost (single-sided moulds)
  • Very large parts are possible
  • Fast for thin packaging
  • Quick, cheap tooling changes
Limits
  • Wall thins as the sheet draws — not uniform
  • Trim waste (the surrounding web)
  • Less fine detail than injection moulding
Typical parts & materials

Typical parts: Food trays and blister packs, cups and lids, vehicle interior panels, signage

Commonly run in — open one for its cited properties:

PSPETPVCABSPMMA

Part of the Make map of manufacturing processes. Browse the cited database, or see where these parts end up in the application domains.