Marine, Shipbuilding & Boat Manufacturing worked example

Marine Weld Labor Estimate at 18% inspection, repair, and downtime allowance: a worked example

Suppose inspection, repair, and downtime allowance falls to 18%. This page works the full calculation at that level so you can see exactly which result moves and by how much. Estimate welding labor hours for steel or aluminum vessel construction based on total weld length, deposition rate, joint preparation factor, and inspection/rework allowance.

The inputs for this scenario

  • Total weld length on the hull or structure: 450 m (held at the documented default)
  • Average weld deposition rate (arc speed): 2.5 m / hr (held at the documented default)
  • Joint preparation and fit-up factor: 2 x (held at the documented default)
  • Inspection, repair, and downtime allowance: 18 % (the input this scenario stresses; the baseline uses 25)

Working through the calculation

  • The calculation starts from the formula this tool documents: Base weld time = total weld length / deposition rate.
  • Total weld labor hours works out to 184 hr at these inputs, and this is the headline figure for the scenario.
  • Base arc-time hours works out to 180 hr at these inputs.
  • Inspection and repair hours works out to 2 % at these inputs.
  • Effective weld completion rate works out to 2.5 pieces / min at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where inspection, repair, and downtime allowance sits at 25% and the headline result is 184 hr, this scenario lands almost exactly on the baseline at 184 hr.
  • It computes total weld labor hours by dividing weld length by deposition rate, scaling for joint prep and fit-up, then adding an inspection and repair allowance. 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

  • Total weld labor hours: 184 hr (headline result)
  • Base arc-time hours: 180 hr
  • Inspection and repair hours: 2 %
  • Effective weld completion rate: 2.5 pieces / min

Run it with your numbers

  • To rerun this with your own numbers, open the live Marine Weld Labor Estimate calculator, set inspection, repair, and downtime allowance to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.