Water, Wastewater & Pump Systems Manufacturing worked example

Corrosion Allowance Cost at 72% share of parts requiring corrosion allowance: a worked example

This worked example runs the corrosion allowance cost numbers for a tougher week than the baseline: 72% share of parts requiring corrosion allowance instead of the typical 100%. Estimate corrosion allowance cost for pump components from part count, added material cost per part, the share needing allowance, and fixed engineering adders.

The inputs for this scenario

  • Pressure-containing parts requiring review: 80 parts (held at the documented default)
  • Added material cost per part for allowance: 45 $ / part (held at the documented default)
  • Share of parts requiring corrosion allowance: 72 % (the input this scenario stresses; the baseline uses 100)
  • Fixed upgrade engineering cost: 900 $ (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Total corrosion allowance cost = pressure-containing parts x added material cost per part x share requiring allowance + fixed upgrade engineering cost.
  • Total corrosion allowance cost works out to 3,492 $ at these inputs, and this is the headline figure for the scenario.
  • Corrosion allowance cost per unit works out to 43.65 $ / piece at these inputs.
  • Variable corrosion allowance cost works out to 2,592 $ at these inputs.
  • Fixed corrosion allowance cost adder works out to 900 $ at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where share of parts requiring corrosion allowance sits at 100% and the headline result is 4,500 $, this scenario comes in 22.4% below the baseline at 3,492 $.
  • Use it when quoting or estimating a job that requires a specified corrosion allowance or upgraded alloy on wetted, pressure-containing parts. 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 corrosion allowance cost: 3,492 $ (headline result)
  • Corrosion allowance cost per unit: 43.65 $ / piece
  • Variable corrosion allowance cost: 2,592 $
  • Fixed corrosion allowance cost adder: 900 $

Run it with your numbers

  • To rerun this with your own numbers, open the live Corrosion Allowance Cost calculator, set share of parts requiring corrosion allowance to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.