Accumulation Conveyor Length & Buffer Calculator

How long does an accumulation conveyor have to be? Long enough to hold every package that arrives while the machine downstream is stopped. Enter the incoming rate, the product length, and the gap products settle to when they close up, then either the seconds of stoppage you must absorb or the conveyor length you already have. The calculator returns the length in feet or the seconds of buffer, the number of products it holds, the count of zero-pressure zones for an MDR accumulation conveyor, and the time to fill the buffer from empty.

Worked example: 40 packages per minute of a 12 in product that closes up to no gap needs 40 × 30 / 60 = 20 products to cover a 30 second stoppage, so 20 × 12 in = 20 ft of accumulation. If the packages settle with a 2 in gap the pitch is 14 in and the length is 23.3 ft. Products round up for length and down for time so the buffer is never short. A 24 in zone length gives ten zero-pressure zones, and at 60 ft/min the belt fills the 20 ft from empty in 20 seconds.

The same math runs the Accumulation card in the Line Flow Simulator, where it uses the rate that survives the splits, merges, and rejects upstream; here it stands alone, and the Use Conveyor Speed infeed button pulls the rate and product length from the infeed card.

How it works
  • Accumulated pitch = product length + the gap products settle to when closed up.
  • Length = ⌈rate (pkg/min) × stoppage (s) / 60⌉ products × pitch. Time = ⌊length / pitch⌋ products / rate × 60.
  • Zero-pressure zones = ⌈length / zone length⌉; time to fill from empty = length / belt speed.
  • Worked example: 40 pkg/min, 12 in product, 30 s → 20 products, 20 ft; with a 2 in settled gap → 23.3 ft.

Free, no login. Your inputs are saved in this browser. Values are engineering references — verify against manufacturer data and applicable codes before a final design.

Built by the engineers behind MDR accumulation conveyors.

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Questions engineers ask

How do I size an accumulation conveyor?
Multiply the incoming rate by the seconds of stoppage you need to absorb, round up to whole products, and multiply by the accumulated pitch (product length plus the settled gap). 40 packages per minute for 30 seconds at a 12 in pitch is 20 products, or 20 ft.
What is zero-pressure accumulation?
An accumulation conveyor whose zones stop individually as product backs up, so packages queue without pushing on each other. Each zone holds one product, so the zone length has to be at least the accumulated pitch, and the zone count is the buffer length divided by the zone length.
How long will my existing conveyor buffer?
Divide its length by the accumulated pitch, round down to whole products, and divide by the rate. A 24 ft conveyor at a 12 in pitch holds 24 products, which is 36 seconds at 40 packages per minute.

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