Welding materials, mechanical properties and chemical composition requirements

1. For ordinary structural steel, weld metal is usually required with the parent material of equal strength, tensile strength should be used is equal to or slightly higher than the base metal of the Welding Electrode 

2. For the alloy structural steel, structural shapes are usually complex, rigid and large thickness of the weldment, the welding process with great stress, easy to weld cracks, should be used in high-stress joints, weld prone to cracking the case of adverse , you can consider using low intensity level than the base metal electrode
3. When the base metal in the carbon and sulfur, high levels of phosphorus and other elements, the weld prone to cracking, good crack resistance should be used with low hydrogen electrode

Weldment performance requirements and working conditions 1. Withstand the impact of dynamic load and load weldment, in addition to meet the strength requirements, but also to ensure that the weld metal has a high impact toughness and ductility, ductility and toughness index should be used with low hydrogen electrode with higher
2. Exposure to corrosive media weldment should be based on the nature of the medium and corrosion characteristics, choose the appropriate type of stainless steel or other corrosion-resistant electrode rod 3. In work under conditions of high or low temperature solder. Low hydrogen Carbon Steel Electrodes for a good crack resistance of the main requirements of the weld metal and base metal alloy composition the same or similar
In the welded structure rigidity,
3. Difficult to clean up the welding parts of the weldment should be used in oxidizing strong, rust, oxide, oil is not sensitive to the acidity of electrode 3. Conditions imposed can not turn on the welding parts, weld in some non-flat welding position, should be used in all-position welding electrode

Construction conditions and equipment 1. In the absence of DC power, and the welded structure has required the use of low hydrogen electrodes must be the occasion should be used in both AC and DC low hydrogen electrode
2. In small or poorly ventilated situations, the choice of acid electrode (silver electrode) or low-dust electrode
Operational process performance to meet the performance and operation process of the condition, try to use low-cost, high efficiency electrode