Thermoforming Draw Ratio & Wall Thickness
Precision Engineering Calculator by Mesoforming
What is Draw Ratio?
Draw Ratio is the relationship between the depth of the part and its opening diameter (H:D). It is the single most important factor in determining whether a product can be formed easily or requires advanced machinery like Mesoforming servo systems.
The "Thinning" Problem
When a plastic sheet is stretched into a mold, the material stretches like a balloon. Without control, the bottom corners of the cup will become extremely thin (Thinning), while the flange remains thick, leading to structural rejection.
Servo Plug Solution
For products with a draw ratio greater than 1.0, standard vacuum forming is insufficient. Mesoforming uses Servo Plug Assist technology to push material into corners with precise speed and depth control.
Часто задаваемые вопросы
Get answers to common engineering questions about thermoforming process optimization and defect prevention.
Why is Draw Ratio important?
It determines the difficulty of forming. Higher ratios require advanced plug assists to prevent wall thinning and ruptures.
What is a safe Draw Ratio?
Generally, a ratio below 0.8 is considered safe for standard forming. Above 1.0 requires plug assist technology.
What materials can be thermoformed?
Common materials include PP, PET, PS, and PLA. Each has different stretching characteristics and heating requirements.
How do I calculate wall thickness?
Use our calculator above. It divides the original sheet volume by the final surface area of the formed part.
What is Servo Plug Assist?
It is a motor-driven plug that mechanically pushes plastic into the mold with precise force control, unlike pneumatic cylinders.
Can I form square trays?
Yes. Select the "Rectangular Tray" tab in the calculator. Square corners are harder to form than round ones.
What causes webbing?
Webbing happens when excess material folds over itself. It is caused by poor material distribution or improper plug design.
How does Mesoforming help?
We provide advanced servo-driven machines and mold designs that optimize material distribution for high-ratio products.
Result showing "Servo Required"?
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