Heat Removal Calculator
Calculate the heat balance of an injection molded part — sensible heat, crystallization latent heat, and the total energy to be removed by the mold cooling system. A key parameter for cooling system sizing.
Input Parameters
Results
Fill in the data and click Calculate
ARGUS automatically balances heat and sizes the mold cooling system
The heat balance is the foundation of cooling system sizing — ARGUS links it with cooling channel geometry, water flow rate, and temperature controller parameters.
How do we calculate the heat balance of a part?
The heat balance of an injection molded part is the total amount of thermal energy that the mold cooling system must remove each cycle. It consists of sensible heat — the energy needed to lower the melt temperature — and latent heat — the energy released during crystallization of semi-crystalline materials.
The calculator applies a full enthalpy balance including crystallization heat for semi-crystalline materials.
Qsensible = m × cp × (Tm − Te)
Qlatent = m × ΔHf × Xc
m — part weight [g]
cp — specific heat [J/(g·K)]
ΔHf — enthalpy of fusion [J/g]
Xc — degree of crystallinity [%]
For amorphous materials (ABS, PC, PS, PMMA) the latent heat is 0 — all energy is sensible heat. For semi-crystalline materials (PP, PA, POM, HDPE) latent heat can account for 20–40% of the total heat balance. Typical enthalpy of fusion values: PP ~210 J/g, PA6 ~230 J/g, POM ~320 J/g.
Cooling system sizing
The heat balance is the starting point for sizing the mold cooling system:
Water Flow Rate = P / (cw × ΔTw) [l/min]
Typical water ΔT — 3–5°C (turbulent flow)
For effective cooling the water flow must be turbulent (Re > 10 000). Laminar flow drastically reduces the heat transfer coefficient. Cooling channel diameter is typically 8–12 mm, with channel-to-cavity-surface distance of 1.5–2.5 × channel diameter.
Cooling optimization
Uneven mold temperature distribution causes warpage and non-uniform shrinkage. For parts with varying wall thickness or complex geometry, consider conformal cooling — channels that follow the cavity shape, produced by metal 3D printing.
ARGUS automatically balances heat and sizes the mold cooling system
See for yourself — book a presentation and explore the full thermal model in ARGUS.