The production technology of the factors affecting the insulation performance of heat shrinkable pipe

So what effect does the manufacturing process have on the insulation performance of the heat shrinkable tube?

In the early stage of the production of insulated heat shrinkable casing, due to the limitation of production process, the insulating heat shrinkable tube can only use wet crosslinking process, which brings a lot of water into the insulation. Practice has proved that for low-voltage products, the insulation heat shrinkable tube produced by this method can also be applied, but should be prudent; For example: four times times military standard heat shrinkable tube, halogen-free non-flame-retardant ultra-thin heat shrinkable tube, when the voltage level exceeds the medium pressure, the safety of the insulated heat shrinkable tube is greatly reduced. With the improvement of the process, the internal and external semi-conductive layer and the insulating layer are now used, and the three layer is extruded at the same time. The advantages are:

(1) It can prevent the introduction of external impurities between the main insulating layer and the conductor shielding, as well as between the main insulating layer and the insulating shielding;

(2) Preventing the conductor shielding and accidental damage that may occur in the main insulating layer during the manufacturing process, thus preventing the formation of spikes due to mechanical damage of the semi-conductive layer;

(3) so that the internal and external shielding and the main insulating layer closely combined, so as to improve the initial free discharge voltage.

When the insulation heat shrinkage pipe is manufactured in different processes, the relationship between the AC breakdown voltage and the thickness of the insulating layer. Thus, it can be seen that the use of extrusion process to manufacture AC breakdown strength is much better than wrapping the semi-conductive belt process.

Therefore, in the selection of heat shrinkable tubes and insulating materials must choose the regular manufacturers.

制造工艺影响热缩管绝缘性能

影响热缩管绝缘性能因素之制作工艺

那么 制造工艺对热缩管绝缘性能有什么影响？

在绝缘热缩套管的生产早期，由于生产工艺限制，使得绝缘热缩管只能使用湿法交联工艺，这给绝缘中带进了大量水分。实践证明，对于低压产品，这种方法生产的绝缘热缩管还能适用，但应慎重;例如：四倍军标热缩管、无卤非阻燃超薄热缩管；当电压等级超过中压时，绝缘热缩管的安全性大为下降。随着工艺改进，现在使用内、外半导电层和绝缘层，三层同时挤出的方法。其优点是:

(1)可以防止在主绝缘层与导体屏蔽，以及主绝缘层与绝缘屏蔽之间引入外界杂质;

(2)在制造过程中防止导体屏蔽和主绝缘层可能发生的意外损伤，因而可以防止由于半导电层的机械损伤而形成突刺;

(3)使内外屏蔽与主绝缘层紧密结合在一起，从而提高起始游离放电电压。

绝缘热缩管用不同工艺制造时，其交流击穿电压与绝缘层厚度的关系。从而可以看出，使用挤出工艺制造交流击穿强度要比包绕半导电带工艺好得多。

所以在选择热缩管和绝缘材料时一定要选择正规厂家。