Industrial Minerals & Powder Processing worked example

Blend Uniformity (CV%) at 37% sample mean: a worked example

This scenario runs the blend uniformity (cv%) calculation on the strong side: 37% sample mean, with every other input held at its documented default. Use it when a quality manager or process engineer needs to verify that a ribbon blender, tumble blender, or continuous mixer is producing a uniform mineral blend within the customer specification (typically CV less than 5% to 10%).

The inputs for this scenario

  • Sample mean (key component): 37 % (raised for this scenario; the documented default is 32.5)
  • Sample standard deviation: 1.8 % (unchanged)
  • Maximum acceptable CV%: 7 % (unchanged)

Working through the calculation

  • Applying the documented formula (Blend CV% = (sample standard deviation / sample mean) x 100) to the inputs above produces each figure below.
  • At this operating point the engine returns 2,056 % for blend cv%, the number this scenario is built around.
  • At this operating point the engine returns -2,049 pp for gap to cv% limit.
  • At this operating point the engine returns 37 % for sample standard deviation.
  • At this operating point the engine returns 1.8 % for sample mean.

How this compares with the baseline

  • Against the tool's baseline example, where sample mean sits at 32.5% and the headline result is 1,806 %, this scenario comes in 13.85% above the baseline at 2,056 %.
  • Use it after pulling stratified samples from a blend to verify mixing before release, or to compare uniformity between blend recipes or mixer settings. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Blend CV%: 2,056 % (headline result)
  • Gap to CV% limit: -2,049 pp
  • Sample standard deviation: 37 %
  • Sample mean: 1.8 %

Run it with your numbers

  • Every input above is editable in the live Blend Uniformity (CV%) calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.