Cooling Time Calculator

Estimate part cooling time from wall thickness, melt temperature, mold temperature, and material thermal properties.

Inputs

Wall Thickness

Melt Temperature

°F

Mold Temperature

°F

Ejection Temperature

°F

Thermal Diffusivity

×10⁻⁷ m²/s

Tab to move between fields

Results

Cooling Time

10.05 sec

Cooling at 50% Thickness2.51 sec

Cooling at 150% Thickness22.61 sec

Melt-to-Mold ΔT180 °C

Cooling as % of Cycle55.7%

How to Use This Calculator

Enter wall thickness (mm) — the thickest cross-section of the part controls cooling time.
Set melt temperature (°C) and mold temperature (°C) for your material and process.
Enter ejection temperature (°C) — the temperature at which the part is stiff enough to eject.
Review calculated cooling time (sec), and how it varies with wall thickness.
Cooling typically represents 50–70% of total cycle time — minimize it by reducing wall thickness.

How the result changes with Wall Thickness

Wall Thickness	Cooling Time
2.95	13.99 sec
9.07	132.27 sec
16	411.63 sec
23	850.59 sec

What each input means

Wall Thickness: Maximum wall thickness of the part in mm.
Melt Temperature: Material melt/injection temperature (e.g., PP: 220, ABS: 230, PC: 300).
Mold Temperature: Mold surface temperature during cooling.
Ejection Temperature: Temperature at which the part is rigid enough to eject.
Thermal Diffusivity: Material thermal diffusivity (PP: 0.9, ABS: 1.1, PA66: 1.5, PC: 1.4).

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Wall Thickness = 2.5, Melt Temperature = 230, Mold Temperature = 50, Ejection Temperature = 90 = 5 input(s) provided
Calculate Cooling Time
Cooling Time = max(round(coolingTimeSeconds * 100) / 100
10.05 = 10.05
Calculate Cooling at 50% Thickness
Cooling at 50% Thickness = max(thinWallTime
2.51 = 2.51
Calculate Cooling at 150% Thickness
Cooling at 150% Thickness = max(thickWallTime
22.61 = 22.61

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