The pros and cons of the extruder screw can be evaluated by the following points:
An extruder screw must first be able to produce products that meet the quality requirements. The so-called meeting quality requirements means that the products produced should meet the following requirements:
1. It has various functions that meet the requirements. It has the required physical, chemical, mechanical, and electrical functions;
2. It has the apparent quality that meets the requirements, for example, it can meet the user's requirements for the uniformity of bubbles, crystal spots, and dyeing dispersion;
3. The plasticizing quality of the extruder screw for sale that meets the requirements:
(1) Whether the temperature of the melt extruded by the extruder screw is uniform, the axial fluctuation, and the radial temperature difference.
(2) Whether there is the lowest melt temperature that can be formed.
(3) Whether the extruded melt is pressure shaken.
(4) Whether the dispersion of dyeing and other additives is uniform.
It should be pointed out that low temperature extrusion is a current development trend. It can improve the quality of extruded products such as reducing internal stress, prevent overheating and differentiation of heat-sensitive materials, reduce energy consumption, reduce the burden on the cooling system of the main and auxiliary machines, and improve production efficiency.
The so-called output value refers to the output value or extrusion volume through a given head under the premise of ensuring the quality of plasticization. As mentioned earlier, the output value is generally expressed in kilograms/hour or kilograms/revolution.
A good extruder screw provided by screw and barrel manufacturer should have high plasticizing ability.
The so-called unit consumption refers to the energy consumed per kilogram of plastic extruded, which is generally expressed by N. In the meantime, N is power (kW) and Q is output value (kg/hour).
The larger the value, the more energy required to plasticize the same weight of plastic. That means the more heating power is consumed, the more mechanical work done by the motor enters the material through shearing and frictional heat. Vice versa.
On the premise of ensuring the quality of plasticization, a good extruder screw unit consumption should be as low as possible.
The so-called adaptability of the screw refers to the adaptability of the extruder screw to process different plastics, match different heads and different products. Generally speaking, the stronger the adaptability, the lower the plasticizing power.
Therefore, we always expect a good screw to have both adaptability and high plasticizing power.
A good extruder screw also needs to be easy to process and low in cost.
The above specifications must be considered together. Emphasizing only one aspect is one-sided. Of course, it is also allowed to focus on ensuring that a certain item meets the specifications for different requirements.