Refractories, Furnace Linings & Foundry Consumables worked example

Gunning Rate at 68% target gunning acceptance rate: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop target gunning acceptance rate to 68%, then walk the calculation through step by step. Gunning rate here measures the share of a gunned refractory surface that comes out defective — delaminations, sags, low density or rebound-scarred zones — against the total area shot.

The inputs for this scenario

  • Rejected or defective gunning area: 8 units (held at the documented default)
  • Total gunned lining area inspected: 250 units (held at the documented default)
  • Target gunning acceptance rate: 68 % (the input this scenario stresses; the baseline uses 95)

Working through the calculation

  • The calculation starts from the formula this tool documents: Gunning Rate rate = affected amount ÷ total amount.
  • Rate works out to 3.2 % at these inputs, and this is the headline figure for the scenario.
  • Gap to target works out to 64.8 points at these inputs.
  • Affected count works out to 8 count at these inputs.
  • Total count works out to 250 count at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where target gunning acceptance rate sits at 95% and the headline result is 3.2 %, this scenario lands almost exactly on the baseline at 3.2 %.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to target gunning acceptance rate, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It is an area-based ratio and doesn't weight by defect severity — a small critical hot-face flaw counts the same as a large cosmetic one.

Results at a glance

  • Rate: 3.2 % (headline result)
  • Gap to target: 64.8 points
  • Affected count: 8 count
  • Total count: 250 count

Run it with your numbers

  • To rerun this with your own numbers, open the live Gunning Rate calculator, set target gunning acceptance rate to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.