Refractories, Furnace Linings & Foundry Consumables worked example

Heat-Up Schedule Duration at 7.2% soak and hold-time allowance: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop soak and hold-time allowance to 7.2%, then walk the calculation through step by step. Heat-Up Schedule Duration estimates how long a controlled refractory dry-out and cure will take, dividing the mass or thickness that must be heated through by the safe controlled ramp rate, then adding an allowance for the isothermal soak holds that a proper dry-out schedule requires.

The inputs for this scenario

  • Total refractory mass or thickness to cure: 120 units (held at the documented default)
  • Controlled ramp rate (cure throughput): 12 units / hr (held at the documented default)
  • Soak and hold-time allowance: 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 heat-up schedule duration 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 soak and hold-time allowance sits at 10% and the headline result is 11 hr, this scenario comes in 2.55% below the baseline at 10.72 hr.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to soak and hold-time allowance, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It models dry-out as a single averaged ramp plus a flat allowance; a real schedule has stepped ramps and multiple soak plateaus, so use this for outage planning, not as the controller setpoint program.

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 Heat-Up Schedule Duration calculator, set soak and hold-time allowance to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.