Welding powder, also known as exothermic flux, is a specialized product for exothermic welding. This welding powder has a fast reaction speed and a strictly designed critical temperature. Depending on the type of solder joint and the metal being welded, the corresponding type of flux needs to be selected. This product adopts double-layer vacuum packaging, which can effectively prevent moisture from affecting the welding effect. Each bag of solder comes with a pack of ignition powder.

The advantages of exothermic welding are:

The current carrying capacity (melting point) of the welding point is equal to the current carrying capacity of the wire;

2. Because the welding points are welded together, they are permanent and will not age;

3. Welding is a permanent molecular bond that will not loosen;

4. Welding points are not affected by corrosive products like copper;

5. The welding point can withstand repeated large surge (fault) currents without degradation;

6. The welding method is simple and easy to train;

7. The materials used for welding are very light and easy to carry;

8. When welding, no external power or heat source is required;

9. The quality of welding can be checked from the appearance;

10. Can be used for welding copper, copper alloys, copper plated steel, various alloy steels including stainless steel, and high resistance heating source materials.

Exothermic welding uses the chemical reaction heat generated when aluminum powder reduces metal oxides as the heat source, and the molten welding powder forms the weld metal with the base metal, which belongs to hot flux welding. This technology is commonly referred to as aluminum thermal welding in railway construction, and the metal oxide in the welding powder is generally iron oxide. The mechanical properties of the welded joint are required to be high. The particularity of the grounding system in power engineering requires the use of materials with lower grounding resistance and greater corrosion resistance. In order to ensure and improve the performance of the grounding system, foreign standards allow the use of copper or copper-clad steel as grounding materials. Therefore, in grounding engineering, the metal oxide of exothermic welding powder is generally copper oxide, which requires high melting point and soil corrosion resistance of the welding joints.

At present, most of the exothermic welding powders used in China are imported products with high prices, which are not conducive to widespread promotion and use. Some domestic manufacturers also produce welding powders with various quality problems, such as low melting points of welding joints, making it difficult to achieve melting points comparable to the base metal; There is splashing during the welding process, which is not conducive to the safety of welding personnel; There are pores and slag inclusions inside the joint. Therefore, developing cost-effective exothermic welding powder products and standardizing joint inspection technical conditions have positive significance for improving the construction quality of power engineering grounding systems and reducing construction costs.