How do you calculate screw conveyor throughput?

Multiply tons per fill cycle by available cycles for gross throughput, then multiply by uptime and yield. Here 18 x 240 = 4,320 gross tons, then x 90% x 96% = 3,732.48 net tons.

What reduces screw conveyor throughput in practice?

Low fill ratio, incline, trough and flight wear, and sticky build-up all cut effective tons per cycle, while jams and clearing cut uptime. In the example, downtime removes 432 tons and off-spec discharge removes 155.52.

What is a good fill ratio for a screw conveyor?

Free-flowing materials run 30-45% trough fill; sticky or fluidizable powders often run lower to avoid packing. Your tons-per-cycle should reflect the fill ratio you can actually sustain, not the maximum.

Why is screw conveyor yield below 100%?

Yield captures material rejected downstream for contamination, moisture, size or degradation. Augers can shear or compact fragile material, so the 96% yield here trims 155.52 tons even though the screw moved the full gross.

Screw conveyor vs belt conveyor throughput, which is higher?

For the same tons-per-cycle and derates the math is identical, but screws are typically chosen for enclosed, shorter, or inclined duty at lower tonnage, where dust control and footprint beat raw belt capacity.

How do I raise net screw throughput?

Attack the bigger loss first. Here the 432-ton uptime gap beats the 155.52-ton yield gap, so reducing jams and clearing time through trough liners and proper fill control returns the most tonnage.

Bulk Solids, Mining, Aggregates & Material Processing calculator

Screw Conveyor Throughput Calculator

Screw Conveyor Throughput estimates the net tonnage an auger actually discharges once you derate its gross fill capacity for downtime and off-spec material. Process engineers handling cement, sand, ash, grain or powders use it to size augers, balance feed to a downstream process, and catch the difference between a screw's rated fill and what truly comes out the discharge. Augers are sensitive to fill ratio, trough wear and sticky build-up, so the uptime and yield derates here often matter more than for an open belt. The split into uptime loss and yield loss shows where to focus.

What this calculator does

Estimate screw conveyor throughput for screw conveyor throughput for bulk solids, mining, aggregates, and material processing using plant-floor material, production, quality, capacity, or cost inputs.
a plant team is reviewing screw conveyor throughput for bulk solids, mining, aggregates, and material processing and needs a clear screw conveyor throughput for production, quality, capacity, maintenance, purchasing, or costing decisions
It multiplies tons per fill cycle by available cycles for gross throughput, then derates by running uptime and on-spec discharge yield for net tons.

Formula used

Gross screw conveyor throughput = screw conveyor throughput output per cycle × available screw conveyor throughput cycles
Screw Conveyor Throughput = gross capacity × uptime × yield

Inputs explained

Tonnage per screw fill cycle:
Screw fill cycles available:
Screw conveyor running uptime:
On-spec discharge yield:

How to use the result

Use it to size a screw conveyor, plan a transfer of bulk powder or aggregate, or reconcile auger discharge against its rated fill capacity.
It assumes a consistent fill ratio. Screw conveyors lose throughput fast when overfilled, when material packs at the trough, or when incline reduces effective fill, none of which a single uptime number captures.

Common questions

How do you calculate screw conveyor throughput? Multiply tons per fill cycle by available cycles for gross throughput, then multiply by uptime and yield. Here 18 x 240 = 4,320 gross tons, then x 90% x 96% = 3,732.48 net tons.
What reduces screw conveyor throughput in practice? Low fill ratio, incline, trough and flight wear, and sticky build-up all cut effective tons per cycle, while jams and clearing cut uptime. In the example, downtime removes 432 tons and off-spec discharge removes 155.52.
What is a good fill ratio for a screw conveyor? Free-flowing materials run 30-45% trough fill; sticky or fluidizable powders often run lower to avoid packing. Your tons-per-cycle should reflect the fill ratio you can actually sustain, not the maximum.
Why is screw conveyor yield below 100%? Yield captures material rejected downstream for contamination, moisture, size or degradation. Augers can shear or compact fragile material, so the 96% yield here trims 155.52 tons even though the screw moved the full gross.
Screw conveyor vs belt conveyor throughput, which is higher? For the same tons-per-cycle and derates the math is identical, but screws are typically chosen for enclosed, shorter, or inclined duty at lower tonnage, where dust control and footprint beat raw belt capacity.

Last reviewed 2026-05-12.