Primary metals · 2025
Foundry throughput recovery
A fictional foundry case study: recovering casting-line capacity by fixing changeover and scrap, without a new furnace.
- Client
- Brackenhill Metals
- Published
Before and after
| Before and after | Before | After |
|---|---|---|
| Overall equipment effectiveness | 61% | 78% |
| Scrap rate | 8.4% | 3.1% |
| Changeover time | 42 min | 18 min |
Context
Brackenhill Metals (fictional) runs a 140,000 tonne-per-year foundry with three casting lines. OEE had drifted to 61%, scrap was above 8%, and the team was preparing a capital request for a fourth furnace.
The plant manager suspected the furnace was the constraint. The production data suggested something else: the line lost more time between casts than during them.
Approach
A two-week diagnostic combined time studies, changeover video, and a scrap Pareto by alloy and shift.
- 38% of changeover delay was waiting for tooling and pre-heat checks that could run in parallel.
- Two alloy grades accounted for 61% of scrap, both linked to a missing pre-cast temperature check.
- The schedule grouped grades in a way that forced unnecessary cleanouts.
We moved pre-heat to a parallel station, built an external setup checklist, and changed the scheduling rule to group compatible grades. No furnace was ordered.
Results
- OEE moved from 61% to 78% over four months.
- Scrap fell from 8.4% to 3.1%.
- Changeover dropped from 42 minutes to 18 minutes.
The capital request was withdrawn. The plant instead spent roughly $180,000 (fictional) on fixtures, a pre-heat station, and operator training.
What changed
The durable change was a ten-minute daily line review with one metric: minutes lost between casts. Six months later, the plant still runs the same checklist and schedule rule.
Fictional case study for portfolio purposes. Client names, sites, and results are invented.