Injection Molding worked example

Mold Parts Per Hour with parts needed per hour of 2,500 parts/hr: a worked example

Push parts needed per hour up to 2,500 parts/hr and the picture changes. This example computes every intermediate figure at that operating point. Use this when scheduling press time, quoting delivery dates, or comparing output rates between mold configurations. Helps determine if a mold can meet hourly or shift targets.

The inputs for this scenario

  • Parts needed per hour (target demand): 2,500 parts/hr (raised for this scenario; the documented default is 1,000)
  • Shots per hour (3600 / cycle time in seconds): 120 shots/hr (unchanged)
  • Number of cavities in the mold: 4 cavities (unchanged)

Working through the calculation

  • Applying the documented formula (Capacity per hour = Shots per hour x Cavities) to the inputs above produces each figure below.
  • At this operating point the engine returns 12,000 parts/hr for good output capacity, the number this scenario is built around.
  • At this operating point the engine returns 300,000 parts/hr for gross capacity.
  • At this operating point the engine returns 288,000 parts/hr for uptime loss.
  • At this operating point the engine returns 0 parts/hr for yield loss.

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 150% above the baseline at 12,000 parts/hr.
  • It computes hourly good-part capacity as shots per hour multiplied by cavities, then compares that capacity against your target demand. 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 output capacity: 12,000 parts/hr (headline result)
  • Gross capacity: 300,000 parts/hr
  • Uptime loss: 288,000 parts/hr
  • Yield loss: 0 parts/hr

Run it with your numbers

  • Every input above is editable in the live Mold Parts Per Hour calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.