Design Guide for PET Thermoformed Medical Device Trays in medical and pharmaceutical: Draft, Radii and Draw Ratio

Thermoforming rewards designs that respect how a heated sheet stretches. These rules prevent most tooling rework and most thickness complaints.

Use it as a working checklist when you write your next enquiry.

Product Overview

This category covers a family of products rather than a single item. In practice a buyer defines thermoformed medical device trays by three things: the base resin, the format or dimension, and the performance or certification level it has to meet. Typical options in this category include gamma, ETO and steam options; gauge 0.40 to 1.50 mm; rigid and semi rigid designs. Materials most often specified are Polycarbonate, Polypropylene, Polyethylene Terephthalate, Polystyrene, and the choice between them changes stiffness, temperature resistance, chemical behaviour and price.

In the medical and pharmaceutical sector the decision is usually driven by validated sealing and sterilisation compatibility, with traceability as a secondary requirement. Typical end uses include diagnostic packs, IV and catheter kits, surgical kit trays.

Key Material Properties

The table below summarises the values that usually decide the material choice.

Polyethylene Terephthalate is frequently the default selection here: High IV PET resin is the reason a 1.5 L bottle can be light yet hold carbonation pressure.

Design Rules for Thermoformed Parts

A few geometry decisions made on the drawing save weeks of tooling adjustment later.

• Use a draft angle of at least 3 degrees per side so the part releases without vacuum locks.
• Make corner radii at least equal to the sheet thickness; sharp corners are where holes start.
• Avoid undercuts unless the tool has moving sections, which adds cost to every cycle.
• Add ribs, steps or kiss-offs instead of increasing overall gauge to gain stiffness.
• Keep the draw ratio moderate: deep cavities thin the sheet and force you to start with a thicker gauge.
• Leave a flat sealing flange of at least 6 mm when the pack has to be heat sealed or lidded.

Send these rules to your designer together with the sheet gauge and the target cycle time; most tooling modifications come from ignoring draft and corner radii.

Common Grades and Variants

• Polypropylene based: lowest density among commodity plastics
• Polystyrene based: rigid and glossy
• Polyethylene Terephthalate Glycol based: excellent clarity with no stress whitening
• Polyethylene Terephthalate based: excellent barrier to CO2 and moisture

Beyond the base resin, most suppliers offer UV stabilised, food contact, flame retardant, anti-static and recycled content versions of the same product. Ask which additive package is included, because it is often the difference between a part that lasts three years and one that lasts ten.

Processing and Finishing Options

The route below is the one most factories use for this type of part.

• Tyvek lidding
• Validation sealing
• Die cutting
• Pressure forming

Secondary operations such as printing, welding, machining and assembly are often cheaper to do in the same factory, and they reduce the risk of mismatch between components.

How to Specify Thermoformed medical device trays Correctly

Work through these points in order and most specification mistakes disappear.

1. specify particle and cleanliness requirements
2. run peel strength testing on every production lot
3. validate the seal process to ISO 11607
4. control tooling wear to avoid trim burrs
5. confirm the sterilisation method with the material

Send this list to your supplier with the drawing and you will receive comparable quotations from every factory you contact.

Frequently Asked Questions

What packing and shipping options are available?

Standard packing is export cartons on fumigation-free pallets, with custom labelling, barcode and retail packing available. We also handle consolidated containers and door to door delivery.

Do you offer samples?

Yes. Standard samples are normally free of charge and shipped within three working days; custom samples are charged at cost and credited against the first production order.

Which certifications can you provide?

We can provide ISO 9001 quality system documentation, material certificates, RoHS and REACH statements, and where applicable food contact, flame retardancy or drinking water approvals. Tell us your target market and we will match the document set.

Can you produce thermoformed medical device trays in Polyethylene Terephthalate?

Yes. {mat1} is one of our regular materials for this item, and we can supply virgin, modified and certified grades with full traceability. Material certificates and test reports are issued per batch.

How long does tooling and sampling take?

A new tool typically takes 25 to 45 days depending on cavity count and complexity, followed by T1 samples within one week. Existing tools can usually start production within 10 to 15 days of order confirmation.

Conclusion

If you are planning a new medical and pharmaceutical project, send us your drawing, annual volume and target properties, and we will come back with a material proposal, a tooling plan and a budget quotation.