Tank Liners polypropylene in 10 mm for Fitness Equipment – Formed to Drawing

These polypropylene tank liners are thick gauge vacuum formed parts supplied to drawing for fitness equipment. They are formed from polypropylene sheet at 10 mm, trimmed on 5-axis routers and inspected against the drawing before packing. Buyers choose this route where a metal fabrication is too heavy, or where injection moulding tooling cannot be justified for the volume.

Product specification

Key features

• One piece shell replaces a fabrication, so assembly hours drop
• polypropylene keeps the weight down while stiffness is held through the formed shape
• As formed gloss finish as standard, further finishes on request
• Trimmed on 5-axis routers, so mounting holes and cut outs match the drawing
• Tooling stored against the part number for repeat and spare orders
• PPAP or ISIR on request

Typical applications

• seat shells
• console housings
• weight stack shrouds
• treadmill motor covers
• tank liners used across general fitness equipment builds

How it is made

1. Parts are inspected, fitted with inserts or hardware if required, packed and shipped.
2. The sheet is formed over the mould with vacuum and, where the draw is deep, with plug assist.
3. The part cools on a jig so the shape is held while the material stabilises.
4. Drawings are reviewed and a manufacturability report is issued with wall thickness, draft and radii marked up.
5. Sheet is dried when the material needs it, then heated to forming temperature on the machine.

Material: polypropylene

Polypropylene survives repeated impact and most cleaning chemicals. Its low forming temperature keeps cycles short, but it shrinks more, so the mould is cut with the shrink factor built in.

Design notes

• avoid sharp steps in the mould, which show as chill marks on the finished surface
• call out the finish on the drawing: mould texture, paint, or as-formed gloss
• use corner radii of at least three times the sheet thickness to avoid thinning
• add ribs or returns instead of increasing sheet thickness to save weight and cycle time

Finishing and assembly options

• as formed gloss
• satin finish
• soft touch coating
• Threaded inserts, PEM fasteners and brackets fitted before dispatch
• Mating parts can be trial assembled before the first article ships

Quality

Sheet thickness is checked on the formed part at the points shown on the drawing, and the readings go into the report. First article inspection covers critical dimensions, wall thickness, colour and texture against the approved sample.

• REACH compliant sheet available
• RoHS compliant grades available
• food contact declarations available

Packing and delivery

Each part is bagged, edges protected with foam, then cartonised for container loading. Standard lead time to first article is 2–3 weeks, and repeat releases ship against stored tooling without a new proving run.

Frequently asked questions

Are spare parts available later?

Tooling is stored against the part number for the life of the programme, so replacements or spare panels can be released at any time.

Can you make it in another material?

Any grade in this family can be swapped in. Send the requirement and the material will be quoted with the price difference shown.

What quantity can I order?

Sample quantities start at one piece off printed tooling. The process pays back from about 25 pieces a year and runs well into several thousand.

Request a quotation

Send the drawing or a photo of the current tank liners with the quantity and the finish required. The reply covers material choice, wall thickness, tooling route and price, so the decision is made on a complete picture.