Rotational Molding worked example

Oven Bottleneck at 65% oven availability × pass rate: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop oven availability × pass rate to 65%, then walk the calculation through step by step. The oven is almost always the pacing station in rotomolding, so its effective throughput sets the ceiling for the whole line.

The inputs for this scenario

  • Good parts cleared through the oven: 1,200 units (held at the documented default)
  • Oven cycle run time: 8 hr (held at the documented default)
  • Oven availability × pass rate: 65 % (the input this scenario stresses; the baseline uses 90)

Working through the calculation

  • The calculation starts from the formula this tool documents: Raw oven bottleneck = completed output ÷ runtime.
  • Effective throughput works out to 97.5 units at these inputs, and this is the headline figure for the scenario.
  • Raw throughput works out to 150 units at these inputs.
  • Efficiency works out to 65 % at these inputs.
  • Runtime works out to 8 hr at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where oven availability × pass rate sits at 90% and the headline result is 135 units, this scenario comes in 27.78% below the baseline at 97.5 units.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to oven availability × pass rate, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It models the oven as a single constraint and will not reveal whether cooling or de-mold stations are actually the tighter bottleneck.

Results at a glance

  • Effective throughput: 97.5 units (headline result)
  • Raw throughput: 150 units
  • Efficiency: 65 %
  • Runtime: 8 hr

Run it with your numbers

  • To rerun this with your own numbers, open the live Oven Bottleneck calculator, set oven availability × pass rate to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.