Selection of welding technology for stainless steel processing

When welding stainless steel, the choice of welding process is very important. Among them, the electrode arc welding process is relatively excellent and is very suitable for processing. Rod arc welding used to be called hand arc welding, which is a commonly used welding method for welding austenitic stainless steel.

The equipment used in arc welding is relatively simple and easy to operate. The equipment is flexible, reliable and adaptable. This is one of the important reasons why it can be used in large quantities. However, the quality of its welded joints depends to a certain extent on the welder's operating skills. Electrode arc welding has poor working conditions and low production efficiency, so it is only suitable for welding single pieces or small batches of products. It is most suitable for short welds, irregular spatial positions and welding joints that are difficult to achieve automated and mechanized welding.

The first is the power source for electrode arc welding. The welding machine used for stainless steel electrode arc welding is the same as ordinary carbon steel electrode arc welding, and must have better characteristics. Both can be used in common, but you must also pay attention to the special features.

First, the price of stainless steel products is high, and the quality requirements for welded joints are high. During welding, the welding machine is required to more reliably ensure stable welding current and arc voltage during the welding process, and the arc is easy to strike and has good combustion stability. Therefore, welding machines with low design and manufacturing standards or that are too broken are not suitable for welding stainless steel materials.

In addition, the current carrying capacity of stainless steel electrodes is lower than that of carbon steel electrodes. The diameter of the electrode is generally below Φ4.0mm. Even if a 5.0mm electrode is used, the welding current is usually controlled at about 200A. The welding current of a small diameter electrode is very low. Therefore, arc welding of stainless steel does not require a high-power welding power source. The performance of those old high-power welding power sources in the small current section is usually not very good and it is difficult to ensure the stability of the arc height. Therefore, it is better to choose a small and medium-power welding machine.

In addition, the process performance of stainless steel electrodes is usually not as good as that of carbon steel electrodes. There are many brands of electrodes suitable for DC, while AC and DC dual-use electrodes are usually used for DC reverse welding, thereby reducing the tendency of porosity. Stainless steel electrode arc welding rarely uses a welding transformer for welding.

Medium and small power DC arc welding generators can be used for arc welding of stainless steel electrodes. The welding process is stable, the arc is easy to start, and is less affected by power grid fluctuations. However, arc welding generators are high-cost, high-energy consumption, and low-efficiency products.

Nowadays, most arc welding of stainless steel electrodes uses rectified DC arc welding power supply. This arc welding rectifier has various functions required by arc welding, has low cost, small no-load power consumption, and low or no noise when in use. This is a relatively energy-saving arc welding power supply.