12 mm polypropylene Seat Shells Manufacturer for Water Treatment

These polypropylene seat shells are thick gauge vacuum formed parts supplied to drawing for water treatment. They are formed from polypropylene sheet at 12 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
• Satin finish 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

• dosing tank liners
• control panel shells
• filter housings
• channel covers
• seat shells used across general water treatment builds

How it is made

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

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

• keep a draft angle of at least 3 degrees on vertical walls so the part releases cleanly
• 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
• call out the finish on the drawing: mould texture, paint, or as-formed gloss

Finishing and assembly options

• satin finish
• anti static coating
• anti graffiti coating
• Threaded inserts, PEM fasteners and brackets fitted before dispatch
• Mating parts can be trial assembled before the first article ships

Quality

Batch releases carry a dimensional report, material certificate and, where agreed, PPAP or ISIR documentation. Moulds, trim fixtures and programmes are stored against the part number, so a repeat order matches the first batch.

• PPAP or ISIR on request
• RoHS compliant grades available
• material certificates with every batch

Packing and delivery

Parts are stacked with interleaved film and packed in export cartons on pallets. Standard lead time to first article is 10–15 working days, 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.

How fast is the first article?

Seven to fifteen working days from drawing release for sample tooling, with production tooling in three to four weeks.

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.

Request a quotation

Send the drawing or a photo of the current seat shells 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.