Abrasive Blasting, Shot Peening & Surface Prep worked example

Part Rotation Time at 14% rigging and safety allowance: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop rigging and safety allowance to 14%, then walk the calculation through step by step. Estimate handling time for rotating or repositioning parts during blast or shot peening cycles.

The inputs for this scenario

  • Reorientations required: 24 rotations (held at the documented default)
  • Reorientation rate per hour: 8 rotations / hr (held at the documented default)
  • Rigging and safety allowance: 14 % (the input this scenario stresses; the baseline uses 20)

Working through the calculation

  • The calculation starts from the formula this tool documents: Base rotation time = required part rotations รท rotation handling rate.
  • Rotation handling time works out to 3.42 hr at these inputs, and this is the headline figure for the scenario.
  • Base rotation time works out to 3 hr at these inputs.
  • Rigging allowance works out to 14 % at these inputs.
  • Rotation handling rate works out to 8 rotations / hr at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where rigging and safety allowance sits at 20% and the headline result is 3.6 hr, this scenario comes in 5% below the baseline at 3.42 hr.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to rigging and safety allowance, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It assumes each reorientation takes about the same effort; a job mixing quick turntable indexes with full crane re-rigs will need a blended rate or it understates the lifts.

Results at a glance

  • Rotation handling time: 3.42 hr (headline result)
  • Base rotation time: 3 hr
  • Rigging allowance: 14 %
  • Rotation handling rate: 8 rotations / hr

Run it with your numbers

  • To rerun this with your own numbers, open the live Part Rotation Time calculator, set rigging and safety allowance to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.