Foundry & Forging worked example

Shot Blast Capacity at 65% shot-blast machine availability: a worked example

Suppose shot-blast machine availability falls to 65%. This page works the full calculation at that level so you can see exactly which result moves and by how much. Estimate good shot-blast or cleaning-machine capacity for castings and forgings.

The inputs for this scenario

  • Parts per blast cycle: 18 parts / cycle (held at the documented default)
  • Available blast cycles: 55 cycles (held at the documented default)
  • Shot-blast machine availability: 65 % (the input this scenario stresses; the baseline uses 90)
  • Accepted blasted-part yield: 97 % (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Gross shot blast capacity = parts per blast cycle × available blast cycles.
  • Good shot blast capacity works out to 624 units at these inputs, and this is the headline figure for the scenario.
  • Gross shot blast capacity works out to 990 units at these inputs.
  • Shot Blast Capacity downtime loss works out to 347 units at these inputs.
  • Shot Blast Capacity reject or rework loss works out to 19.31 units at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where shot-blast machine availability sits at 90% and the headline result is 864 units, this scenario comes in 27.78% below the baseline at 624 units.
  • It computes good (sellable) shot blast capacity by discounting gross blast throughput for machine availability and accepted-part yield. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • Good shot blast capacity: 624 units (headline result)
  • Gross shot blast capacity: 990 units
  • Shot Blast Capacity downtime loss: 347 units
  • Shot Blast Capacity reject or rework loss: 19.31 units

Run it with your numbers

  • To rerun this with your own numbers, open the live Shot Blast Capacity calculator, set shot-blast machine availability to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.