Irradiation cross-linked low-smoke halogen-free flame-retardant power electric radiation cross-linked low-smoke halogen-free flame-retardant power wires and cables are widely recognized by the majority of electricians and electrical practitioners due to their excellent comprehensive electrical and physical properties, and they are the main project of the Beijing Olympic Games , Beijing’s Great Hall of the People and other large-scale national landmark buildings have been applied, showing good market prospects. But what is worrying is that some imitations or even counterfeiting of this product have been discovered in recent years, which seriously threatens the quality and image of construction projects. In view of this situation, the following provides some simple methods for identifying radiation cross-linked low-smoke halogen-free flame-retardant wires and cables for reference:
1. Product name recognition method
Wire radiation cross-linked low-smoke halogen-free flame-retardant polyethylene insulated power wire and cable; cable radiation cross-linked low-smoke halogen-free flame-retardant polyethylene insulated low-smoke halogen-free flame-retardant polyethylene sheathed power cable. Imitation products generally have a slightly different name, such as irradiated cross-linked polyethylene insulated low-smoke halogen-free sheathed flame-retardant power cable and so on.
2. Skin burn method
There should be no obvious depression in the insulating layer with an electric soldering iron. If there is a large depression, it means that the material or process of the insulating layer is defective. Or use a lighter for barbecue. Normally, it should not be easy to ignite. After a long period of burning, the insulation layer of the cable is still relatively intact, without heavy smoke and pungent smell, and the diameter has increased. If it is easy to ignite, it can be determined that the insulation layer of the cable does not use low-smoke halogen-free materials (probably polyethylene or cross-linked polyethylene materials). If there is a lot of smoke, it means that the insulating layer uses halogen-containing materials. If the insulation surface falls off severely after burning for a long time, and the diameter does not increase significantly, it means that the appropriate irradiation cross-linking process has not been performed.
3. Hot water immersion method
Soak the core or cable in hot water at 90℃, under normal circumstances, the insulation resistance will not drop rapidly and stay above 0.1MΩ/Km. If the insulation resistance drops rapidly or even lower than 0.009MΩ/Km, it means that it has not been treated by a suitable radiation crosslinking process. (Polyethylene or cross-linked polyethylene insulation material does not apply to this method for identification, and can be identified by the method in the second above).
4. Density contrast method
The density of low-smoke halogen-free materials is higher than that of water, so you can peel off a little insulation layer and put them in the water. If they float above the water surface, they are definitely not low-smoke halogen-free materials.
