Sendemory Metal Products Co., Ltd.

Characteristics of low-smoke halogen-free cable materials The formula of low-smoke halogen-free cable materials is relatively unique. In the base material
However, due to the large filling amount of low-smoke halogen-free cable materials and the relatively large viscosity of the melt, during production Screw rotation and shearing, as well as friction between low molecular materials, between low molecular materials and screws, barrels, and between low molecular materials and polymers are more serious than other cable materials, which will generate a large amount of heat, causing the extruder to Rapid temperature rise can easily cause the flame retardant to decompose in advance and produce pores.
Generally, low-smoke halogen-free cable materials will soften at ℃ and can be extruded at ~℃. However, the products of some manufacturers have a higher usage ratio, high melt viscosity, and require higher temperatures for extrusion. Cable factories that are not familiar with the situation will extrude cables at low temperature and low speed, which will cause the production speed to decrease and the efficiency to decrease. At the same time, the various properties of the material cannot be fully displayed. Extrusion equipment The most basic and versatile equipment for wire and cable extrusion molding is the single-screw extruder. The screw is the most important component of the extruder, which is related to the application range and production efficiency of the extruder. In view of the high filling of low-smoke halogen-free cable materials, a lot of heat is generated due to shearing during production, which requires a better cooling system to cool down. At the same time, the extrusion die corresponding to the cable is also the key to the success of cable extrusion.
Cooling device of the extruder During the extrusion process, due to the particularity of low-smoke halogen-free cable materials, the molten material generates a large amount of heat due to friction, which requires the extrusion equipment to have a good cooling device. To control the process temperature. This is a problem that cannot be ignored. If the temperature is too high, large pores will be formed on the surface of the cable. If the temperature is too low, the overall current of the device will increase, which can easily damage the device. I once saw a cable factory in Shanghai change the air cooling of the extruder cooling system to a water cooling system. After the change, the temperature rise was a bit slow, but the temperature rise was steady, the cooling speed was fast, and the system temperature was stable. . There are many filling materials in the extrusion die for low-smoke halogen-free cable materials, which results in large differences in the strength, draw ratio and viscosity of the melt in the molten state from other cable materials, so the selection of molds is also different. .


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