1. Different materials need to use barrel screws with d […]
1. Different materials need to use barrel screws with different structures.
2. Different barrel screws are required to produce different products.
3. The same raw materials, but the quality of the raw materials has changed, and the requirements for the barrel screw will also be different.
Here are the references:
(I) Production The so-called production refers to the production or extrusion of a given handpiece under the premise of ensuring the quality of plasticizing. As mentioned earlier, the output is generally expressed in kilograms per hour or kilograms per revolution. A good screw should have a high plasticizing capacity. (Production capacity) It should be pointed out that low temperature extrusion is a current development trend, which can improve the quality of extruded products (such as reducing internal stress, etc.), prevent thermal decomposition of heat sensitive materials, reduce energy consumption, and reduce the cooling system of main and auxiliary machines. Burden and increase productivity.
(II) Quality of plasticizing A screw must first be able to produce products that meet the quality requirements.
The so-called quality requirement means that the products produced should meet the following requirements:
1. Have a variety of performances that meet the requirements. Having compliant physical, chemical, mechanical, and electrical properties;
2, with the appropriate quality of the requirements. If the user can meet the requirements of bubbles, crystal points, dye dispersion uniformity and so on.
3. Plasticizing quality of the screw with the requirements: 1) Whether the temperature of the melt extruded by the screw is uniform, axial fluctuation, and radial temperature difference. 2) Is there a minimum melt temperature that can be formed? 3) Whether the extruded melt has pressure fluctuations. Whether the dispersion of dyeing and other additives is uniform or the like.
(3) Unit consumption Unit consumption refers to the energy consumed per kilogram of plastic (rubber), which is generally expressed by N. Where N is the power (kW) and Q is the production (kg/hr). The larger the value, the more energy is required to plasticize the same weight of plastic (rubber), which means that the more heating power is consumed, the mechanical work done by the motor enters the material in the form of shear and frictional heat. many. vice versa. A good screw, under the premise of ensuring the quality of plasticization, the unit consumption should be as low as possible.
(IV) Adaptability The so-called screw adaptability refers to the adaptability of the screw to the processing of different plastics, matching different heads and different products. In general, the more adaptable, often accompanied by a decrease in plasticizing efficiency. Therefore, we always hope that a good screw should have both adaptability and high plasticizing efficiency.
(5) Difficulties in manufacturing A good screw must also be easy to manufacture and manufacture at a low cost.