Generally use the heat shrink sleeve do not know the insulation material of the production of heat shrink tube purification and mixing principle, the following Kehong heat shrink pipe network small catalog for you to state the purification and mixing of insulation materials.

XLPE insulation is a mixture of polyethylene resin, cross-chain agent and anti-aging agent, which requires the ingredients to be clean, free of conductive and harmful impurities, and to mix evenly and well dispersed. Mixing unevenly, poorly dispersed mixtures accelerate local aging and increase water absorption. If the anti-aging agent is unevenly dispersed, it can also lead to a decrease in electrical performance.

There are two kinds of impurities in the insulation, both foreign and self-contained. Foreign impurities contain small amounts of mixed metal powders, fibrous hairs and other conductive impurities. Self-producing impurities include a charred PE resin (dark yellow, called a "fire beat") and an anti-aging agent, Bloom. Conductive impurities can cause a sharp increase in the strength of local electric fields. For electrical performance alone, the size of impurities (and voids) must be limited to a range of operating voltages that do not cause local discharge. Assuming that the impurity is an ellipse floating in the insulation, when the average field strength of the cable is 93 kV/mm and the ellipse's long-axis ratio is 10: 1, the maximum electric field strength of the elliptic tip will rise to 193 kV/mm, 50 times the average electric field strength. The hazards of conductive impurities are related not only to particle size, but also to the shape of impurities and their orientation in the electric field. However, the very fine impurities, its shape and orientation on the strength of the electric field is not too big. Because its impact area and high field energy are very small, there is no obvious effect on insulation, media strength.

Since the discovery of the phenomenon of water trees, the above-mentioned design judgments on impurities and voids have exposed certain deficiencies, especially for insulation above 35 k V is more obvious. To prevent and reduce water trees, cables above 35 kV are best used with dry cross chains and clean (or ultra-clean) PE materials.

In order to prevent the dispersion of the mixture unevenly and mixed into foreign impurities, the production plant must use a special closed material handling system. Ingredients, mixing and extrusion must be limited to the current three mixing methods, with the second extruded mixing granulation method is the most common.

绝缘材料的净化和混合

一般使用热缩套管的不知道制作热缩管的绝缘材料的净化和混合原理，下面柯鸿热缩管网小编为你陈述绝缘材料的净化和混合。

XLPE绝缘料是由聚乙烯树脂、交链剂以及防老剂等组成的混合物，要求各项成分洁净，不含导电及有害杂质，并要求混合均匀且分散良好。混合不均，分散不良的混合料会加速局部老化和增大吸水性。如果防老剂分散不均也会导致电性能下降。

绝缘料的杂质有外来和自生两种。外来杂质含有少量混入的金属粉末、纤维细毛及其他导电杂质。自生杂质有焦烧的PE树脂(色深黄，称作“火拍”)和析出的防老剂“结花”(Bloom)。导电杂质能导致局部电场强度急剧升高。仅从电性能考虑，必须把杂质(及空隙)的大小限制在工作电压下不会导致局部放电的范围以内。假定杂质是一个浮悬在绝缘中的椭圆体，当电缆的平均场强是93 kV/ mm，椭圆的长短轴比是10 : 1时，椭圆尖端的最高电场强度将升至193 kV/ mm，是平均电场强度的50倍。导电杂质的危害性不仅与颗粒大小有关，还与杂质的形状和在电场中的取向有关。但极微细的杂质，其形状和取向对电场强度的影响都不太大。因为它的影响面积和高场强的能量都很微小，对绝缘、介质强度没有明显影响。

自从发现水树现象以后，上述有关杂质和空隙的设计判断就暴露出一定不足之处，特别对35 k V以上的绝缘更为明显。为防止和减少水树现象，35 kV以上的电缆最好用干法交链和洁净(或超净)的PE材料。

为了防止混合物分散不均和混入外来杂质，生产工厂必须采用一种专用的密闭材料处理系统。配料、混合、挤出必须限当前三种混炼方法，以第二种挤出混炼造粒法用得最为普遍。