Reasons for Thermal Elongation Testing of XLPE Insulation

Cables have a very large proportion in life. 

As a common insulating material for cables, XLPE is often mentioned. 

For example, CU XLPE SWA PVC cable, 33kv XLPE copper cable, and aluminum XLPE ABC cable.

1 Crosslinked polyethylene (XLPE) is used as a polyolefin material. 

XLPE is a cable insulation made of a special low-density polyethylene (PE)-based resin, a peroxide system, an anti-oxidation system, etc., which is made by a special process. 

Polyethylene modified by the cross-linking method has greatly improved its comprehensive properties such as mechanical properties, environmental stress cracking resistance, chemical corrosion resistance, creep resistance, and electrical properties. 

Moreover, the cross-linked polyethylene cable is rapidly developed due to its light structure, simple construction, easy operation, maintenance, etc., especially in the production of power cables in China, and therefore has a large development space.

2 Cross-linked polyethylene (XLPE) not only maintains good physical and mechanical properties before polyethylene (PE) cross-linking, excellent chemical stability, and excellent dielectric properties but also improves long-term use temperature (from the original 70~ C is increased to 90~C).

And environmental stress cracking, creep resistance and other physical and mechanical properties are improved. 

Cross-linked polyethylene is more resistant to acid and alkali and oil than polyethylene, and its olefinic product is also C0. 

And H. 0, so the harm to the environment when burning is very small, in line with the requirements of modern fire, low smoke, and non-toxic, is the first choice for environmentally friendly cable materials.

3 Thermal extension test of cross-linked polyethylene material Organic peroxide chemical crosslinking, silane warm water crosslinking, and electron radiation crosslinking are the most commonly used methods for producing cross-linked cables.

4. The size of the thermal extension reflects the degree of cross-linking of XLPE insulation at high temperatures. 

The standard specifies the mandatory test for cross-linked cables.