Injection Molding worked example

Mold Parts Per Hour with parts needed per hour of 500 parts/hr: a worked example

This worked example runs the mold parts per hour numbers for a tougher week than the baseline: parts needed per hour of 500 parts/hr instead of the typical 1,000 parts/hr. Calculate parts per hour output from cycle time and mold cavitation to plan production capacity and press scheduling.

The inputs for this scenario

  • Parts needed per hour (target demand): 500 parts/hr (the input this scenario stresses; the baseline uses 1,000)
  • Shots per hour (3600 / cycle time in seconds): 120 shots/hr (held at the documented default)
  • Number of cavities in the mold: 4 cavities (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Capacity per hour = Shots per hour x Cavities.
  • Good output capacity works out to 2,400 parts/hr at these inputs, and this is the headline figure for the scenario.
  • Gross capacity works out to 60,000 parts/hr at these inputs.
  • Uptime loss works out to 57,600 parts/hr at these inputs.
  • Yield loss works out to 0 parts/hr at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where parts needed per hour sits at 1,000 parts/hr and the headline result is 4,800 parts/hr, this scenario comes in 50% below the baseline at 2,400 parts/hr.
  • Use it when quoting a new part, validating that a cycle time hits the required annual volume, or deciding how many cavities to cut into a new mold. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Good output capacity: 2,400 parts/hr (headline result)
  • Gross capacity: 60,000 parts/hr
  • Uptime loss: 57,600 parts/hr
  • Yield loss: 0 parts/hr

Run it with your numbers

  • To rerun this with your own numbers, open the live Mold Parts Per Hour calculator, set parts needed per hour to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.