The size of the melt length of the plastic strand pelletizer directly affects the quality of the pellets. The melt length is the distance at which the melting of the plastic material occurs during the heating and extrusion process. So, what are the main factors that affect the melt length of plastic granulator equipment?
Influence of plastic properties
The interaction of the thermal and rheological parameters of plastics makes the melt length of plastics in a plastic strand pelletizer subject to a number of influences. By understanding and adjusting these parameters, melt length can be better controlled. It should be noted that different types of plastics have different characteristics. Therefore, the specific type of plastic needs to be considered when selecting and operating a granules extruder machine.
Effect of process conditions
The extrusion flow rate Q is proportional to the melt length. In addition, an increase in Q leads to an increase in the delay effect. That is, the onset and completion of melting is delayed and the range of end temperature fluctuations is greater. Other things being equal, product quality deteriorates with increasing flow rate. Therefore, in order to increase the flow rate, the length of the compression section needs to be increased accordingly. Otherwise, the quality of the product decreases.
Plastic strand pelletizer Screw Diameter
The size of the plastic strand pelletizer screw diameter affects the extrudability of the plastic and therefore the melt length.