Heat Treatment, Furnaces & Thermal Processing worked example

Batch Heat Treat Capacity at 99% furnace uptime: a worked example

Push furnace uptime up to 99% and the picture changes. This example computes every intermediate figure at that operating point. Use it when a batch furnace, vacuum furnace, oven, or atmosphere furnace must prove it can cover scheduled demand.

The inputs for this scenario

  • Parts per furnace load: 250 parts / load (unchanged)
  • Usable furnace loads: 6 loads / shift (unchanged)
  • Furnace uptime: 99 % (raised for this scenario; the documented default is 88)
  • First-pass heat treat yield: 96 % (unchanged)

Working through the calculation

  • Applying the documented formula (Gross batch capacity = parts per furnace load × usable furnace loads) to the inputs above produces each figure below.
  • At this operating point the engine returns 1,426 parts / shift for good batch heat treat capacity, the number this scenario is built around.
  • At this operating point the engine returns 1,500 parts / shift for gross batch capacity.
  • At this operating point the engine returns 15 parts / shift for furnace downtime loss.
  • At this operating point the engine returns 59.4 parts / shift for quality yield loss.

How this compares with the baseline

  • Against the tool's baseline example, where furnace uptime sits at 88% and the headline result is 1,267 parts / shift, this scenario comes in 12.5% above the baseline at 1,426 parts / shift.
  • It computes good parts-per-shift by multiplying load size and loads per shift, then derating for furnace uptime and first-pass yield. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Good batch heat treat capacity: 1,426 parts / shift (headline result)
  • Gross batch capacity: 1,500 parts / shift
  • Furnace downtime loss: 15 parts / shift
  • Quality yield loss: 59.4 parts / shift

Run it with your numbers

  • Every input above is editable in the live Batch Heat Treat Capacity calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.