Metals, Steel, Aluminum & Coil Processing worked example

Rolling Mill Throughput at 65% mill efficiency: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop mill efficiency to 65%, then walk the calculation through step by step. Estimate rolling mill throughput by dividing tons rolled by run time and applying a realistic mill efficiency, then compare it to the pace you need to commit.

The inputs for this scenario

  • Tons rolled: 600 tons (held at the documented default)
  • Mill run time: 8 hr (held at the documented default)
  • Mill efficiency: 65 % (the input this scenario stresses; the baseline uses 90)

Working through the calculation

  • The calculation starts from the formula this tool documents: Rolling throughput = tons rolled รท run time.
  • Effective tons per hour works out to 48.75 tons/hr at these inputs, and this is the headline figure for the scenario.
  • Raw throughput works out to 75 tons/hr at these inputs.
  • Mill efficiency works out to 65 % at these inputs.
  • Run time works out to 8 hr at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where mill efficiency sits at 90% and the headline result is 67.5 tons/hr, this scenario comes in 27.78% below the baseline at 48.75 tons/hr.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to mill efficiency, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. A single efficiency factor lumps together all delay and speed-loss causes; for root-cause work you need a full OEE breakdown of availability, performance, and quality rather than one blended number.

Results at a glance

  • Effective tons per hour: 48.75 tons/hr (headline result)
  • Raw throughput: 75 tons/hr
  • Mill efficiency: 65 %
  • Run time: 8 hr

Run it with your numbers

  • To rerun this with your own numbers, open the live Rolling Mill Throughput calculator, set mill efficiency to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.