Heat Treatment, Furnaces & Thermal Processing calculator

Annealing Cycle Time Calculator

Add the actual heating, hold, cooling and handling stages for consecutive annealing loads. Use the approved recipe and occupancy logs for this furnace and load family.

What this calculator does

  • Plan furnace occupancy for serial annealing loads from the actual recipe stages.

Formula used

  • Cycle hours per load = heat-up + qualified hold + occupied cooling + handling
  • Scheduled hours = planned loads × cycle hours per load
  • Total hold = loads × hold; total occupied cooling = loads × occupied cooling
  • Window margin = available furnace hours − scheduled hours

Inputs explained

  • Planned Loads: Whole furnace charges on the production schedule.
  • Heat-Up Time per Load: Logged heating and equalization time for this load family.
  • Qualified Hold per Load: Required hold after the approved load temperature is reached.
  • Occupied Cooling per Load: Cooling time while the load still occupies this furnace.
  • Handling Time per Load: Non-overlapping charging, discharge and reset time from logs.
  • Available Furnace Window: Scheduled hours available for these consecutive loads.

How to use the result

  • Best suited to serial annealing load schedules, cooling occupancy comparisons.
  • Does not determine temperature, cooling rate or metallurgical hold requirements. Queue time before furnace entry is excluded.

Current U.S. benchmarks

  • Industrial electricity averages 9.77 cents per kWh across the U.S. (EIA, Jul 2026), up 4.7% from a year earlier. Energy-intensive steps carry this directly into unit cost.

Common questions

  • When does the hold start? Start the qualified hold only after the load meets the temperature condition in its approved process instruction.
  • Should I include overnight cooling? Include it if the load occupies the furnace overnight. Exclude time spent cooling elsewhere.
  • Can several furnaces share these loads? This model assumes one furnace. Split the loads into separate schedules when furnaces operate in parallel.
  • Are the default hours a recipe? No. Replace them with approved stage durations or comparable furnace records for your alloy, geometry and loading arrangement.

Last reviewed 2026-10-06.