Grain Milling, Dry Bulk Food & Feed Handling worked example

Grind Size Distribution at 98% sieve test efficiency factor: a worked example

What does the result look like when sieve test efficiency factor reaches 98%? The full calculation is worked below with real intermediate numbers. Use it when quality or production needs to understand how quickly hammer mill, roller mill, pellet crumble, or flour particle-size samples can be checked during a run.

The inputs for this scenario

  • Ground sample weight tested: 24 lb (unchanged)
  • Particle-size sieve test runtime: 2 hr (unchanged)
  • Sieve test efficiency factor: 98 % (raised for this scenario; the documented default is 85)

Working through the calculation

  • Applying the documented formula (Raw grind-size test throughput = sample weight tested ÷ particle-size test runtime) to the inputs above produces each figure below.
  • At this operating point the engine returns 11.76 lb / hr for effective throughput, the number this scenario is built around.
  • At this operating point the engine returns 12 lb / hr for raw grind-size test throughput.
  • At this operating point the engine returns 98 % for efficiency.
  • At this operating point the engine returns 2 hr for runtime.

How this compares with the baseline

  • Against the tool's baseline example, where sieve test efficiency factor sits at 85% and the headline result is 10.2 lb / hr, this scenario comes in 15.29% above the baseline at 11.76 lb / hr.
  • A figure at this level is achievable when sieve test efficiency factor is genuinely sustained, not just peaked for a shift. It treats efficiency as a flat factor and does not model sieve blinding, static, or fines that distort heavier samples — it sizes lab throughput, not the accuracy of the distribution itself.

Results at a glance

  • Effective throughput: 11.76 lb / hr (headline result)
  • Raw grind-size test throughput: 12 lb / hr
  • Efficiency: 98 %
  • Runtime: 2 hr

Run it with your numbers

  • Every input above is editable in the live Grind Size Distribution calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.