Plastics Extrusion - Pipe, Film & Profile worked example

Line Speed By Wall Thickness at 99% cooling and sizing efficiency: a worked example

What does the result look like when cooling and sizing efficiency reaches 99%? The full calculation is worked below with real intermediate numbers. Use it when pipe wall thickness, sheet gauge, or profile section size changes and the team needs a realistic line speed.

The inputs for this scenario

  • Good extruded length: 1,800 ft (unchanged)
  • Elapsed run time: 60 min (unchanged)
  • Cooling and sizing efficiency: 99 % (raised for this scenario; the documented default is 92)

Working through the calculation

  • Applying the documented formula (Raw line speed by wall thickness = good extruded length ÷ elapsed run time) to the inputs above produces each figure below.
  • At this operating point the engine returns 29.7 ft / min for usable line speed, the number this scenario is built around.
  • At this operating point the engine returns 30 ft / min for calculated line speed before losses.
  • At this operating point the engine returns 99 % for cooling and sizing efficiency.
  • At this operating point the engine returns 60 min for elapsed run time.

How this compares with the baseline

  • Against the tool's baseline example, where cooling and sizing efficiency sits at 92% and the headline result is 27.6 ft / min, this scenario comes in 7.61% above the baseline at 29.7 ft / min.
  • A figure at this level is achievable when cooling and sizing efficiency is genuinely sustained, not just peaked for a shift. The efficiency factor is a single lumped derate — it does not model tank length, water temperature, or vacuum level, so it guides rather than replaces a proper cooling calculation.

Results at a glance

  • Usable line speed: 29.7 ft / min (headline result)
  • Calculated line speed before losses: 30 ft / min
  • Cooling and sizing efficiency: 99 %
  • Elapsed run time: 60 min

Run it with your numbers

  • Every input above is editable in the live Line Speed By Wall Thickness calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.