Grain Milling, Dry Bulk Food & Feed Handling worked example

Screen Change Impact at 97% post-change milling efficiency: a worked example

Push post-change milling efficiency up to 97% and the picture changes. This example computes every intermediate figure at that operating point. Use it when changing screen size, mesh, perforation, or classifier setup and you need to understand the capacity effect before committing a grind-size or product change.

The inputs for this scenario

  • Output after screen change: 96 tons (unchanged)
  • Runtime on new screen: 8 hr (unchanged)
  • Post-change milling efficiency: 97 % (raised for this scenario; the documented default is 84)

Working through the calculation

  • Applying the documented formula (Raw screen-change throughput = output after screen change รท runtime on new screen) to the inputs above produces each figure below.
  • At this operating point the engine returns 11.64 tons / hr for effective throughput, the number this scenario is built around.
  • At this operating point the engine returns 12 tons / hr for raw screen-change throughput.
  • At this operating point the engine returns 97 % for efficiency.
  • At this operating point the engine returns 8 hr for runtime.

How this compares with the baseline

  • Against the tool's baseline example, where post-change milling efficiency sits at 84% and the headline result is 10.08 tons / hr, this scenario comes in 15.48% above the baseline at 11.64 tons / hr.
  • It computes the effective tons-per-hour a line runs on a newly installed screen by dividing post-change output by post-change runtime and derating by the resulting milling efficiency. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Effective throughput: 11.64 tons / hr (headline result)
  • Raw screen-change throughput: 12 tons / hr
  • Efficiency: 97 %
  • Runtime: 8 hr

Run it with your numbers

  • Every input above is editable in the live Screen Change Impact calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.