2.2.1 Enthalphy Curves For Various Thermoplastics

Enthalpy curve for various thermoplastics diagram.

How to use :

Read out on the corect material curve the enthalpy in Kcal/kg and multiply this with the used material quantity in kg/h, you get the :

(Kcal/ kg)/(kg/h)  =  Kcal/h

Wich are needed to cool down the melt material in the mold during production.

For example :

- material : PS
- shot weight : 100 g   100 shot/h
- demolding temperatur : ca. 30 C
- 210 C = 85 Kcal/kg
-   30 C = 5 Kcal/kg ==> 85 - 5 = 80 Kcal/kg

Enthalpy = (80 Kcal/kg) . (0.1 kg/h) . 100 = 800 Kcal/h

For summer temperatur in Northern Europe, you must add up approx 25 - 30 % to have enough capacity at your cooling equiepment. A mold with hotrunner needs an extra cooling of approx. 25 - 30%.