Manufacturing Processes - Vacuum Forming

Vacuum Forming

Vacuum Forming Process

The vacuum forming process comes under the general manufacturing processes category of forming. The process involves producing components that are formed by heat softening plastic sheet and forcing it against the form of a cooled mould using a vacuum to pull the material to the mould. Once shaped it is allowed to cool.

There are many similarities between vacuum forming and superplastic forming with respect to the the tools used for the process. There are, as with the superplastic forming, three primary processes for vacuum forming:

  • Vacuum Forming, where a heat softened sheet of plastic is clamped over a female die and a vacuum is pulled underneath the sheet to pull it into the dies cavity profile to take the shape of the die cavity.
  • Drape Forming, a heat softened plastic sheet is placed over a male die and a vacuum is pulled through the die to draw the sheet over the profile to form the shape of the component.
  • Plug Assist Vacuum Forming, this is where a heat softened plastic sheet is pushed into a die cavity using a mechanical male plug or plunger to assist. Once the first stages shaping has taken place using the plug, a vacuum is drawn through the die to pull the plastic sheet into the die cavity to create the final form.

The process is used to produce 3D shapes with what are effectively constant section thickness's with no re-entrant angles. There is significant molecular orientation that takes place in amorphous thermoplastics and good surface texture is achieved. Albeit that reproduction of fine details are limited.

The tooling is relatively inexpensive although fully automated machines are expensive. The cycle times are dependent on the heating and cooling times of the plastic sheet. Using the automated machines reduces cycle times.

Vacuum forming is suitable for processing most thermoplastic materials.

Vacuum Forming

Plastic Thermoforming
Plastic Thermoforming

Plastic thermoforming is the process of producing parts by heating and shaping plastic sheet and film. Using shop floor footage and detailed animations, this program highlights both cut sheet and roll fed thermoforming operations, and features segments on clamping systems, heating systems, thermoforming mold types, forming forces, and trimming processes.

 
The Prop Builder's Molding & Casting Handbook
The Prop Builder's Molding & Casting Handbook

Demonstrates how to work with moulds, castings, and vacuum forming equipment, stresses safety precautions, and discusses materials from paper-mache to breakaway glass.

 
Technology of Thermoforming
Technology of Thermoforming

This handbook offers an overview of all technical aspects of thermoforming. Covers polymeric materials, heating the sheet, cooling and trimming the Part, thermoforming molds, parts design, setup protocols, troubleshooting and economics of thermoforming. DLC: Plastics - Molding.

 

Vacuum Forming - Simplicity Itself

Vacuum Forming - Your Comments

No comments yet.

    Sign in or sign up and post using a HubPages Network account.

    0 of 8192 characters used
    Post Comment

    No HTML is allowed in comments, but URLs will be hyperlinked. Comments are not for promoting your articles or other sites.


    More by this Author


    Click to Rate This Article
    working