Instructions for using carbon steel welding rods:

Welding Electrode specifications

Instructions for using carbon steel welding rods:
Implement GB/T5117-1995 standard
Carbon steel welding rods are suitable for welding carbon steel and low strength low-alloy steel.
The selection of welding rods is based on the requirements of the chemical composition, mechanical properties, and crack resistance of the steel, as well as a comprehensive analysis of factors such as welding structure, steel plate thickness, working conditions, stress conditions, and welding machine performance. When necessary, conduct welding tests, develop corresponding process measures, and then determine the selection of welding rods.
1. Welding of carbon steel generally uses welding rods that correspond to the strength grade of the steel. At the same time, considering complex structures, thick plates, high stiffness, dynamic loads, and poor weldability, low hydrogen welding rods with good plasticity, high impact toughness, and good crack resistance are generally selected. For welding positions with special requirements, corresponding specialized welding rods should be used, such as vertical downward welding rods, bottom welding rods, etc. Iron powder type welding rods can be used to improve welding efficiency.
2. For welding seams with fast cooling speed, increased strength, and easy cracking, welding rods with one level lower strength than the base metal can be used; The welding of dissimilar steels between low carbon steel and low alloy steel generally uses welding rods corresponding to the lower strength grade of the steel, and considers the factor of low alloy steel, so it is advisable to choose low hydrogen type.
3. For the welding of medium carbon steel, due to the high carbon content of the steel, the tendency for welding cracks is increased. Generally, low hydrogen type welding rods are used, and preheating, slow cooling and other methods as well as corresponding welding processes are adopted.
4. Cast steel has poor weldability, generally high carbon content, thick workpiece, complex structure, and is prone to welding cracks. When there are many alloying elements in cast steel, it becomes more prominent. Generally, low hydrogen welding rods are used, and preheating, slow cooling, and corresponding welding processes are adopted.
To ensure welding quality, the welding joints of the workpiece should be cleaned thoroughly and free from oil stains, rust, moisture, paint, and dirt. It is particularly important to use low hydrogen welding rods.
For low hydrogen type welding rods, they must be baked at 350 ℃ for 1 hour before welding and used immediately after baking, otherwise defects such as porosity, slag inclusion, and cracks may occur. Cellulose welding rods generally do not need to be baked. If they become damp, they should be baked according to the temperature specified in the manual before welding. However, if the temperature is too high, it will damage the welding process performance of the welding rod.
The welding current specified in the manual is a reference value, which should be carefully controlled in actual operation. For example, when preheating the workpiece, it can be 5% to 15% lower than the normal current; Vertical welding and overhead welding have a current 10% to 15% lower than flat welding; When using DC, it can reduce by about 10% compared to AC. When using a DC welding machine, pay attention to the welding grade specified in the manual, otherwise it will affect the welding process.Low hydrogen type welding rods should generally not be repeatedly baked to prevent the coating from becoming brittle or falling off.