Fastening, Torque & Joint Assembly worked example

Bolt Preload Estimate at 11% setup, access, and retest allowance: a worked example

This worked example runs the bolt preload estimate numbers for a tougher week than the baseline: 11% setup, access, and retest allowance instead of the typical 15%. Estimate the time needed to complete bolt preload verification from joint count, verified checks per hour, and setup or retest allowance.

The inputs for this scenario

  • Bolts or joints needing preload verification: 120 joints (held at the documented default)
  • Verified preload checks per hour: 18 checks / hr (held at the documented default)
  • Setup, access, and retest allowance: 11 % (the input this scenario stresses; the baseline uses 15)

Working through the calculation

  • The calculation starts from the formula this tool documents: Base preload verification time = bolts or joints needing verification รท verified preload checks per hour.
  • Required preload verification hours works out to 7.4 hr at these inputs, and this is the headline figure for the scenario.
  • Base verification hours works out to 6.67 hr at these inputs.
  • Setup/access allowance works out to 11 % at these inputs.
  • Preload verification rate works out to 18 checks / hr at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where setup, access, and retest allowance sits at 15% and the headline result is 7.67 hr, this scenario comes in 3.48% below the baseline at 7.4 hr.
  • Use it when planning preload audits for a build batch, sizing torque-tech labor for a shift, or quoting verification coverage for a structural or pressure-containing assembly. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Required preload verification hours: 7.4 hr (headline result)
  • Base verification hours: 6.67 hr
  • Setup/access allowance: 11 %
  • Preload verification rate: 18 checks / hr

Run it with your numbers

  • To rerun this with your own numbers, open the live Bolt Preload Estimate calculator, set setup, access, and retest allowance to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.