Rail Signaling & Wayside Equipment worked example

Rework Cost at 50% share of flags confirmed as real defects: a worked example in rail signaling & wayside equipment

This worked example runs the rework cost numbers for a tougher week than the baseline: 50% share of flags confirmed as real defects instead of the typical 70%. Estimate the cost to rework defective rail signaling and wayside assemblies from the count flagged, per-unit correction cost, and confirmed defect rate.

The inputs for this scenario

  • Assemblies flagged for rework: 120 units (held at the documented default)
  • Rework labor & materials per assembly: 340 $/unit (held at the documented default)
  • Share of flags confirmed as real defects: 50 % (the input this scenario stresses; the baseline uses 70)
  • Line setup & retest charge: 2,500 $ (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Rework cost = flagged assemblies x rework cost per unit x confirmation rate% + setup/retest.
  • Total rework cost works out to 22,900 $ at these inputs, and this is the headline figure for the scenario.
  • Rework cost per unit works out to 191 $ / piece at these inputs.
  • Variable rework cost works out to 20,400 $ at these inputs.
  • Fixed rework cost adder works out to 2,500 $ at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where share of flags confirmed as real defects sits at 70% and the headline result is 31,060 $, this scenario comes in 26.27% below the baseline at 22,900 $.
  • Use it after a batch of signaling assemblies is flagged in functional test or commissioning, to size the rework bill and compare rework against scrap or resource. 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

  • Total rework cost: 22,900 $ (headline result)
  • Rework cost per unit: 191 $ / piece
  • Variable rework cost: 20,400 $
  • Fixed rework cost adder: 2,500 $

Run it with your numbers

  • To rerun this with your own numbers, open the live Rework Cost calculator, set share of flags confirmed as real defects to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.