Rotational Molding worked example

Delivery Capacity at 65% machine uptime: a worked example in rotational molding

Here is what the math looks like when conditions slip. We hold every other input steady and drop machine uptime to 65%, then walk the calculation through step by step. Delivery Capacity tells you how many good, shippable parts a rotomolding line can commit to over a planning period after uptime and yield losses.

The inputs for this scenario

  • Good parts per oven cycle: 4 units / cycle (held at the documented default)
  • Available oven cycles in the period: 480 cycles (held at the documented default)
  • Machine uptime: 65 % (the input this scenario stresses; the baseline uses 90)
  • First-pass yield: 97 % (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Gross delivery capacity capacity = units per cycle × available cycles.
  • Good output capacity works out to 1,211 units at these inputs, and this is the headline figure for the scenario.
  • Gross capacity works out to 1,920 units at these inputs.
  • Uptime loss works out to 672 units at these inputs.
  • Yield loss works out to 37.44 units at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where machine uptime sits at 90% and the headline result is 1,676 units, this scenario comes in 27.78% below the baseline at 1,211 units.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to machine uptime, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It uses period-average uptime and yield, so it will not capture a bad week where a mold problem tanks yield below the average you entered.

Results at a glance

  • Good output capacity: 1,211 units (headline result)
  • Gross capacity: 1,920 units
  • Uptime loss: 672 units
  • Yield loss: 37.44 units

Run it with your numbers

  • To rerun this with your own numbers, open the live Delivery Capacity calculator, set machine uptime to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.