Spare-Parts Stock Planning: Hedging Downtime with Inventory
Three Spare Classes
| Class | Examples | Strategy |
|---|---|---|
| Critical | Lasers, PSUs, boards, handpieces | Don’t stockpile expensive units — secure a “rapid access agreement” (vendor stock + delivery SLA) |
| Wear items | Filters, seals, tubing, lamps, fuses | Safety stock by consumption cycle, swap on failure |
| Common | Screws, cables, connectors | Small standing stock, replenished with PM |
Setting Safety Stock
- Burn rate: historical monthly usage from the ledger.
- Replenishment lead time: vendor dispatch + shipping.
- Safety stock = daily burn × lead time × risk factor (1.5-2).
For critical parts, the “stock” is access speed: written delivery SLAs with the vendor for common criticals (e.g., 48 h), verified against a real regional parts warehouse (the parts dimension of service evaluation).
Stock Discipline
- Check-ins and withdrawals logged, linked to device dossiers.
- Electronics stored dry and static-safe; rubber parts rotated by age.
- Quarterly stocktake plus vendor stock-list refresh.
FAQ
Should we stockpile a spare laser?
Usually no — expensive, storage-sensitive, low unit failure rates. The right hedge: negotiate a “backup laser clause” at purchase (vendor-held commitment or swap-time guarantee).
Spare parts for discontinued models?
Negotiate post-discontinuation supply years at purchase (the consumable clauses); near end-of-life, lock criticals via one final bulk order.