Skip to content
Automotive & Mobility · Bratislava, Slovakia · 2025

A topcoat line was losing 4.2% of bodies to visible paint defects, with root cause disputed between paint supply, booth air and circulation filtration.

Defect rate after rollout
1.2%
Reduction in rework
71%
Trial to plant-wide decision
6 weeks
Annualised rework saving
€2.4M

The challenge

The plant's rework bay was running at capacity on a 4.2% defect rate. Three parties each held a different theory. Nobody had characterised what the defects actually were, which meant every proposed fix was a guess with a budget attached.

How we approached it

  1. 01Defect particles were physically recovered from rejected panels and analysed by SEM-EDX to identify composition and size.
  2. 02Analysis showed 68% of defects were polyester fibre — matching the sewn seams of the incumbent circulation filter bags.
  3. 03Booth air and paint circulation were each sampled independently to rule out the other contributors.
  4. 04Welded-seam absolute-rated bags were trialled on one line for six weeks before plant-wide rollout.

What we delivered

Replacement of sewn-seam felt bags with STRATA welded-seam, calendered, absolute-rated 25 µm bags across all paint circulation loops, together with an upgrade of booth supply air to F9 with sealed header frames.

Nobody had put a defect under a microscope in two years of arguing about it. That single analysis ended the debate in an afternoon.
Paint Shop Manager · European automotive OEM

Project facts

Client
European automotive OEM
Industry
Automotive & Mobility
Location
Bratislava, Slovakia
Year
2025

Measured results

1.2%
Defect rate after rollout
71%
Reduction in rework
6 weeks
Trial to plant-wide decision
€2.4M
Annualised rework saving

Next step

Tell us what is in the stream.

Flow rate, contaminant, target rating, chemistry and available pressure. Six inputs, and our engineers return a staged design with the sizing basis attached — typically inside 48 hours.

Or call +91 79 4890 2200 · sales@worldasatech.com