Scope of this guide
This management guide translates the process into cost, risk and throughput: what to measure, what to audit and where the money leaks.
Process: Barrel Plating. Figures in this guide are industry-standard starting ranges; confirm against your supplier TDS before locking settings.
Working ranges and control points
The table below is the daily reference for a plating barrel. Set by the card, verify by the control point column.
| Parameter | Typical range | Control point | Watch out |
|---|---|---|---|
| Loading ratio | 15–30% of barrel volume | Parts tumble freely | Overload gives flat spots |
| Barrel speed | 4–8 rpm | Full tumble visible | Too fast burns parts at door |
| Current per load | 2–6 A/dm² equivalent | Amp-min per kg logged | High current burns outer parts |
| Contact danglers | 2 per barrel, clean tips | Contact resistance < 0.1 Ω | Worn danglers give no-plate zones |
| Cycle time | 20–45 min by thickness | Thickness spot-check per run | Long cycles wear media |
Run It As A Business: the management view
Beyond the basic card, this is the layer that matters at your level:
| Cost line | What drives it | Metric to track | Typical lever |
|---|---|---|---|
| Chemicals | Drag-out and bath dumps | Cost per 1000 parts | Rinse counter-flow, drip bars |
| Rework | First-pass yield losses | FPY by defect family | Fix top family first |
| Energy | Heated tanks and idle time | kWh per 1000 parts | Covers, night setback |
| Claims | Escape rate | PPM by customer | Ship gate on FPY |
Standard routine
- Weigh the load and set amp-min target
- Check dangler tips for clean metal contact
- Set barrel speed by part size and weight
- Sample thickness at cycle end, one part per 10 kg
- Rinse in-barrel before unload to protect colour
Engineer notes
- Mixed sizes plate unevenly — split loads by part family
- Amp-min per kg, not amp-min per barrel, is the real dose
- Burn marks collect on parts resting at the barrel door
- Add media balls for flat parts to prevent sticking
- Log every load; trend dose vs thickness weekly
Safety: Barrels are heavy and hot after plating. Use hoists and heat gloves; never lift a barrel by its door.
FAQ
Why do some parts in one load come out thin?
They sat against the door or centre of the mass. Check dangler contact and reduce load size.
What loading ratio should I start with?
15–30% of barrel volume so parts tumble freely; flat parts need less.
How often should dangler tips be cleaned?
Daily, and replaced weekly in high-current work.
Which single metric should I start reporting weekly?
First-pass yield by defect family; it exposes rework cost and points at the largest lever.