Rate questions sound hard until they become arithmetic. Three numbers — speed, gap and item length — decide what any conveyor lane can carry.
The only formula you need
Items per hour equals speed divided by pitch, times 3,600. Pitch is item length plus the gap between items, in metres. A 0.5 m carton with a 0.3 m gap on a 1.0 m/s belt: 1.0 / 0.8 × 3,600 = 4,500 cartons per hour. Everything else is refinement.
Gaps are where rate hides
Doubling belt speed doubles wear and noise; tightening gap control often buys the same rate for free. This is why sorter infeeds obsess over induction — metering items to a steady pitch is worth more than raw speed.
Merges and curves set the ceiling
A line is only as fast as its slowest junction. Rate the merge first, then match the straights to it — a 4,500-per-hour belt feeding a 2,800-per-hour merge is a queue, not a line.
Keep 20% in reserve
Design at 80% of theoretical capacity. The margin absorbs mis-gapped items, re-circulations and the growth your sales team is promising.
