Injection Molding worked example

Mold Cavitation with annual part demand of 1,000,000 parts/year: a worked example

Suppose annual part demand falls to 1,000,000 parts/year. This page works the full calculation at that level so you can see exactly which result moves and by how much. Determine the optimal number of mold cavities from annual demand, available press cycle time, and production hours.

The inputs for this scenario

  • Annual part demand: 1,000,000 parts/year (the input this scenario stresses; the baseline uses 2,000,000)
  • Available production hours per year: 6,000 hrs/year (held at the documented default)
  • Cycle time per shot: 25 sec (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Shots per year = Available hours x 3600 / Cycle time.
  • Good output capacity works out to 1,500,000,000 cavities at these inputs, and this is the headline figure for the scenario.
  • Gross capacity works out to 6,000,000,000 cavities at these inputs.
  • Uptime loss works out to 4,500,000,000 cavities at these inputs.
  • Yield loss works out to 0 cavities at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where annual part demand sits at 2,000,000 parts/year and the headline result is 3,000,000,000 cavities, this scenario comes in 50% below the baseline at 1,500,000,000 cavities.
  • It computes the minimum number of mold cavities required to meet annual part demand given your usable press hours and cycle time per shot. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • Good output capacity: 1,500,000,000 cavities (headline result)
  • Gross capacity: 6,000,000,000 cavities
  • Uptime loss: 4,500,000,000 cavities
  • Yield loss: 0 cavities

Run it with your numbers

  • To rerun this with your own numbers, open the live Mold Cavitation calculator, set annual part demand to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.