Material Handling

Line Side Inventory Sizing

Size line-side inventory with cycle stock, a late-run buffer, and a safety margin, not cycle stock alone, which understates real stockout risk.

Run frequencyminutes between milk-run deliveriesConsumption rateunits/hour consumed at the line

Sizing buffers

Replenishment intervalminutes from triggering a run to its arrivalSafety factorfraction, buffer added on top of cycle stock plus lead-time bufferUnit footprintsq ft occupied per unit carried at the line

Line-side inventory108 units

Footprint54 sq ft

Cycle stock60

Lead-time buffer30

Safety stock18

Resources

Guide Line-Side Inventory and Milk-Run Design A replenishment loop works when delivery frequency, line-side capacity, and consumption variability are planned together.

How this works

Cycle stock covers consumption between scheduled runs; the lead-time buffer covers consumption during the time a triggered run takes to actually arrive; safety stock is a percentage margin on top of both, covering variability in consumption or run timing.

Key terms

Cycle stock: inventory consumed between scheduled milk-run deliveries.
Lead-time buffer: extra inventory covering the time between triggering a run and its arrival.

Assumptions

Steady consumption rate, uniform run frequency and lead time

Limitations

Single line-side location, not a full kanban-loop card-count sizing

Sources

Standard point-of-use / line-side inventory sizing practice.

Worked example

A cycle-stock-only estimate reports 60 units needed, 30 sq ft. The correct sizing, cycle stock plus a 30-unit lead-time buffer plus an 18-unit safety margin, totals 108 units and 54 sq ft, a 45% understatement the cycle-stock-only view misses.

Common use cases

Sizing point-of-use inventory and its floor footprint at a production line
Setting min/max levels for a line-side kanban location
Avoiding a stockout risk from an undersized cycle-stock-only estimate