How to extend the service life of 304 stainless steel pipe

Laser Welding of 304 Stainless Steel Tube Welding Methods In recent years, as manufacturers have become more concerned about environmental issues, automobile manufacturers are under increasing pressure to improve fuel efficiency. More stringent and more restrictive regulations pose technical challenges for industrial production and material processing. Among these trends are reduced emissions, lighter bodies and longer component life.

Advances in material processing have created unique opportunities for the production of stainless steel tubes. Specifically, manufacturers are required to produce such parts that must have a lighter weight, but must still have corrosion protection characteristics and meet strength requirements. In addition, the space limitations of the body emphasize the importance of formability. Typical applications include exhaust pipes, fuel lines, fuel injectors, and other components.

In the case of a stainless steel tube, a flat steel strip is first formed, and then its shape is rounded. Once formed, the seams of the stainless steel tubing must be welded together. This weld greatly affects the formability of the part. Therefore, in order to obtain a welding profile that meets the stringent testing requirements of the manufacturing industry, it is extremely important to choose the right welding technology. Undoubtedly, tungsten gas shielded arc welding (GTAW), high frequency (HF) welding, and laser welding have been used in the manufacture of stainless steel tubes.

  Laser welding

In all 304 stainless steel tube welding applications, the edges of the steel strip are melted and the edges solidify when the edges of the stainless steel welded tubes are pressed together using a clamping bracket. However, a unique property for laser welding is its high energy beam density. The laser beam not only melts the surface of the material, but also creates a keyhole so that the weld is very narrow.

If the power density is less than 1 MW/cm2, such as GTAW technology, sufficient energy density cannot be produced to produce a keyhole. Thus, the keyless hole process results in a wide and shallow weld profile. The high precision of laser welding results in higher efficiency penetration, which in turn reduces grain growth and results in better metallographic quality; on the other hand, GTAW's higher thermal input and slower cooling process result Rough welded structure.