The raw materials used in ERW steel pipes are hot-rolled coils produced by regular large factories, and the chemical composition and physical properties are relatively stable.Most of the raw materials used in the spiral tube factory are low-grade hot-rolled strip steel, the chemical composition and physical properties are not stable, and there are many internal defects and impurities.

The seamless steel pipe has a hollow section and is widely used as a pipeline for transporting fluids, such as pipelines for transporting oil, natural gas, gas, water and certain solid materials. Compared with ordinary seamless pipes, stainless steel seamless pipes have higher corrosion resistance, and the finish is better than ordinary seamless steel pipes. But this does not mean that stainless steel seamless pipes will not be corroded.

Stainless steel rectangular pipe is a kind of hollow long steel, which is widely used as pipeline for transporting fluids, such as oil, natural gas, water, gas, steam, etc. In addition, when the bending and torsional strengths are the same, the weight is lighter.Therefore, it is also widely used in the manufacture of mechanical parts and engineering structures. It is also commonly used to produce various conventional weapons, barrels, shells, etc.

Seamless pipe is the most used pipe fitting in oil and gas engineering pipelines and construction engineering pipelines. The pressure rating design of seamless pipe is introduced below. The pressure rating of seamless pipe includes two parts: the nominal pressure rating of standard pipe fittings expressed in nominal pressure. ;Wall thickness class of standard fittings expressed in wall thickness class

SSAW Tube and LSAW Tube are carbon steel tubes using submerged arc welding technology. Submerged arc welding is a welding method in which the arc burns under the flux layer. Its inherent advantages of stable welding quality, high welding productivity, no arc and little smoke make it the main welding method in the production of important steel structures such as pressure vessels, pipe sections, box beams and columns.

The main factors affecting the cracking of seamless steel pipes include the defect of the original material and the influence of metallographic structure on the cracking of seamless steel pipes