1.Why are thick-walled straight seam steel pipes magnetic?

Thick-walled straight seam steel pipes are generally not magnetic or weakly magnetic, but if they are magnetic, they will not affect us during use, but for many manufacturers, it is still necessary to clean the magnetic properties of thick-walled straight seam steel pipes.

The magnetic properties of thick-walled straight seam steel pipes are caused by the magnetism of martensite or ferrite. Due to improper segregation of components or heat treatment during the movement, a small amount of martensite or ferrite will be formed in the austenitic 304 stainless steel, thereby weakening the magnetic properties of the thick-walled straight seam steel pipe.

2. How to solve the existence of magnetism in thick-walled straight seam steel pipes?

In order to solve the magnetic properties of thick-walled straight seam steel pipes formed due to the above reasons, the recovery and stabilization arrangement of austenite can be opened through high-temperature solution treatment, thereby solving the magnetic performance problems, especially due to the above reasons, thick-walled straight seam steel pipes The magnetic properties of seam steel pipes and other stainless steel raw materials, that is, thick-walled straight seam steel pipes, show weak magnetic properties.

In addition, the structure of thick-walled straight seam steel pipes will also be transformed into martensitized due to cold working. The greater the degree of cold deformation, the greater the martensite transformation, and the better the magnetic energy of the thick-walled straight seam steel pipe. Like the same batch of steel strips, the Φ76 tube has no obvious magnetic induction, and the Φ9.5 tube is produced. Due to the large magnetic induction of cold bending deformation, the deformation of the square rectangular tube is greater than that of the round tube, especially the corner deformation is larger. The deformation of thick straight seam steel pipes is stronger and more magnetic than that of round pipes.