Refractories, Furnace Linings & Foundry Consumables worked example

Dryout Time at 7.2% hold-step allowance for safe moisture release: a worked example

This worked example runs the dryout time numbers for a tougher week than the baseline: 7.2% hold-step allowance for safe moisture release instead of the typical 10%. Dryout Time estimates how long a controlled heat-up must run to safely drive physically and chemically held water out of a cured refractory lining before the furnace goes to service temperature.

The inputs for this scenario

  • Bound and free water to drive off (equivalent work): 120 units (held at the documented default)
  • Controlled heat-up drying rate: 12 units / hr (held at the documented default)
  • Hold-step allowance for safe moisture release: 7.2 % (the input this scenario stresses; the baseline uses 10)

Working through the calculation

  • The calculation starts from the formula this tool documents: Base dryout time time = required work รท processing rate.
  • Adjusted run time works out to 10.72 hr at these inputs, and this is the headline figure for the scenario.
  • Base run time works out to 10 hr at these inputs.
  • Allowance applied works out to 7.2 % at these inputs.
  • Process rate works out to 12 pieces / min at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where hold-step allowance for safe moisture release sits at 10% and the headline result is 11 hr, this scenario comes in 2.55% below the baseline at 10.72 hr.
  • Use it after cure is complete to plan the heat-up ramp and hold schedule that removes water from the lining. 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

  • Adjusted run time: 10.72 hr (headline result)
  • Base run time: 10 hr
  • Allowance applied: 7.2 %
  • Process rate: 12 pieces / min

Run it with your numbers

  • To rerun this with your own numbers, open the live Dryout Time calculator, set hold-step allowance for safe moisture release to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.