How do you calculate bulk solids shrinkage?

Find gross tonnage as output per cycle times available cycles, then apply availability and retained-material yield. At 18 tons/cycle x 240 cycles x 90% x 96% the net retained tonnage is 3,732.48 tons against a 4,320-ton gross.

What causes shrinkage in bulk material handling?

Airborne dust at transfer points, belt spillage and carryback, degradation of friable material into unsaleable fines, moisture loss, and residual cling in silos and hoppers. Most terminals find transfer points are the dominant source.

What is a typical bulk solids shrinkage percentage?

For well-controlled dry handling, 1-3% total shrinkage is good; 3-6% is common with open transfer points. The default here implies about 13.6% combined availability and yield loss, which would flag a handling system needing attention.

Is shrinkage the same as moisture loss?

No. Moisture loss is one component, but shrinkage also includes dust, spillage, degradation and residual cling. A material can gain apparent shrinkage purely from drying out in storage even with zero spillage.

How do I reduce conveying losses?

Target the biggest yield drains first: enclose and skirt transfer chutes, add belt cleaners for carryback, control dust at load-out, and reduce drop heights to limit degradation. Each point of retained yield recovered here adds straight to shipped tons.

Bulk solids shrinkage vs moisture correction?

Moisture correction removes water to find dry tons; shrinkage accounts for physical material that leaves the system as dust, spillage and degradation. Both shrink the saleable figure but for different, separately fixable reasons.

Bulk Solids, Mining, Aggregates & Material Processing calculator

Bulk Solids Shrinkage Calculator

Bulk solids shrinkage is the tonnage that quietly disappears as granular material moves through conveyors, transfer points, silos and load-out, lost to dust, spillage, degradation and carryback. Plant managers in cement, grain, fertilizer, frac sand and mineral handling track it because shrinkage shows up as a stubborn gap between tons received and tons shipped, eroding margin without ever appearing on a single invoice. Quantifying it turns a vague inventory loss into a number you can target with skirting, dust collection and transfer-point redesign. On a large terminal, a few points of shrinkage is real money walking off the belt.

What this calculator does

Estimate bulk solids shrinkage for bulk solids shrinkage for bulk solids, mining, aggregates, and material processing using plant-floor material, production, quality, capacity, or cost inputs.
a plant team is reviewing bulk solids shrinkage for bulk solids, mining, aggregates, and material processing and needs a clear bulk solids shrinkage for production, quality, capacity, maintenance, purchasing, or costing decisions
It computes the net tonnage retained after handling, by applying conveying availability and first-pass retained yield to gross cycle output.

Formula used

Gross bulk solids shrinkage = bulk solids shrinkage output per cycle × available bulk solids shrinkage cycles
Bulk Solids Shrinkage = gross capacity × uptime × yield

Inputs explained

Net product tonnage per handling cycle:
Available handling or transfer cycles in the period:
Conveying and storage availability:
First-pass retained-material yield:

How to use the result

Use it when reconciling inbound versus outbound inventory, budgeting expected handling losses, or building a business case for dust and spillage control.
It captures aggregate shrinkage as a yield factor and will not tell you where along the handling chain the material is being lost; a mass-balance survey is needed to localize the leak.

Common questions

How do you calculate bulk solids shrinkage? Find gross tonnage as output per cycle times available cycles, then apply availability and retained-material yield. At 18 tons/cycle x 240 cycles x 90% x 96% the net retained tonnage is 3,732.48 tons against a 4,320-ton gross.
What causes shrinkage in bulk material handling? Airborne dust at transfer points, belt spillage and carryback, degradation of friable material into unsaleable fines, moisture loss, and residual cling in silos and hoppers. Most terminals find transfer points are the dominant source.
What is a typical bulk solids shrinkage percentage? For well-controlled dry handling, 1-3% total shrinkage is good; 3-6% is common with open transfer points. The default here implies about 13.6% combined availability and yield loss, which would flag a handling system needing attention.
Is shrinkage the same as moisture loss? No. Moisture loss is one component, but shrinkage also includes dust, spillage, degradation and residual cling. A material can gain apparent shrinkage purely from drying out in storage even with zero spillage.
How do I reduce conveying losses? Target the biggest yield drains first: enclose and skirt transfer chutes, add belt cleaners for carryback, control dust at load-out, and reduce drop heights to limit degradation. Each point of retained yield recovered here adds straight to shipped tons.

Last reviewed 2026-05-12.