Injection Molding worked example

Plastic Regrind Savings with annual regrind used in production of 37,500 kg/year: a worked example

This scenario runs the plastic regrind savings calculation on the strong side: annual regrind used in production of 37,500 kg/year, with every other input held at its documented default. Use this when building a business case for a granulator purchase, evaluating cold runner vs. hot runner economics, or reporting material cost reductions to management.

The inputs for this scenario

  • Annual regrind used in production: 37,500 kg/year (raised for this scenario; the documented default is 15,000)
  • Savings per kg (virgin price minus regrind cost): 1.2 $/kg (unchanged)
  • Quality/yield derating factor: 0.95 x (unchanged)

Working through the calculation

  • Applying the documented formula (Annual savings = Regrind consumption x Cost savings per kg x Quality factor) to the inputs above produces each figure below.
  • At this operating point the engine returns 42,750 $ for result, the number this scenario is built around.
  • At this operating point the engine returns 42,750 value for gross savings (volume x cost difference).
  • At this operating point the engine returns 1 x for multiplier.
  • At this operating point the engine returns 45,000 value for factor a x b.

How this compares with the baseline

  • Against the tool's baseline example, where annual regrind used in production sits at 15,000 kg/year and the headline result is 17,100 $, this scenario comes in 150% above the baseline at 42,750 $.
  • Use it to build the business case for a granulator or recycling program, or to quantify savings already captured by an existing regrind loop. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Result: 42,750 $ (headline result)
  • Gross savings (volume x cost difference): 42,750 value
  • Multiplier: 1 x
  • Factor A x B: 45,000 value

Run it with your numbers

  • Every input above is editable in the live Plastic Regrind Savings calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.