Detailed introduction

27

2018

-

07

Which kind of screw is better for film blowing machine


How to choose a film blowing machineScrewWhat?
1. Different raw materials need to choose different structure of the barrel screw.
2. The production of different products need to choose different barrel screw.
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) yield The so-called yield refers to the yield or extrusion of a given head under the premise of ensuring the quality of plasticization. As mentioned earlier, production is generally expressed in kg/hour or kg/turn. A good screw should have a high plasticizing capacity. (Production capacity) It should be noted that low-temperature extrusion is a development trend at present, which can improve the quality of extruded products (such as reducing internal stress, etc.), prevent overheating and decomposition of heat-sensitive materials, reduce energy consumption, reduce the burden of cooling system of main and auxiliary machines, and improve productivity.
(II) plasticizing quality A screw must first be able to produce products that meet the quality requirements.
The so-called quality requirements refers to the production of products should meet the following requirements:
1. It has various properties that meet the requirements. Having the required physical, chemical, mechanical and electrical properties;
2, with the requirements of the apparent quality. Such as can meet the user's requirements for bubbles, crystal points, dyeing and dispersion uniformity, etc.
3. The plasticizing quality of the screw that meets the requirements: 1) Whether the temperature of the melt extruded by the screw is uniform, the axial fluctuation, and the radial temperature difference. 2) Whether there is the lowest melt temperature to be molded. 3) Whether the extruded melt has pressure fluctuations. Whether the dispersion of dyeing and other additives is uniform, etc.
(III) unit consumption refers to the energy consumed per kilogram of plastic (rubber) extruded, generally expressed in N. where N is power (kW) and Q is output (kg/h). The larger this value, the more energy is required to plasticize the same weight of plastic (rubber), which means that the more heating power is consumed, and the more mechanical work done by the motor enters the material through shear and friction heat. And 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 adaptability of the so-called screw refers to the adaptability of the screw to process different plastics, match different heads and different products. Generally speaking, the stronger the adaptability, the lower the plasticizing efficiency. Therefore, we always hope that a good screw, its adaptability and high plasticizing efficiency should be both.
(V) is difficult to manufacture a good screw must also be easy to manufacture, low cost.