Processing Technology of Hot-Rolled Stainless Steel Seamless Pipe

Stainless steel seamless pipes can be divided into hot-rolled stainless steel seamless pipes, cold-rolled stainless steel seamless pipes, cold-drawn stainless steel seamless pipes, and extruded stainless steel seamless pipes according to different production methods. The processing of hot-rolled stainless steel seamless pipes is a complex process that requires multiple steps to transform the stainless steel blank into the final seamless pipe product. The following are the general processing steps of hot-rolled stainless steel seamless pipes.

Raw material preparation:

The starting material is usually stainless steel blanks, which can be round or square in cross-section. These blanks are usually prepared at room temperature, in a hot rolling or forging process.

Hot rolling:

The stainless steel billet is fed into the hot rolling mill, heated to high temperatures, and then rolled through multiple rolls to gradually reduce the cross-sectional size and finally form a tube shape. This process is usually carried out at high temperatures to ensure that the stainless steel has enough plasticity to allow smooth shape adjustment.

Perforation:

After the hot-rolled stainless steel blank is formed into a tube shape, it needs to be processed (perforated) to form the inner hole of the seamless tube. This process is carried out using a punch machine, usually at high temperatures, to ensure a seamless finish.

Stretching and diameter reduction:

After the seamless pipe is perforated, it usually needs to go through multiple stretching and diameter reduction processes to adjust its outer diameter and wall thickness. This helps meet pipe specifications.

Heat treatment:

Seamless pipes are solution annealed in a heat treatment furnace to eliminate residual stress, improve mechanical properties and improve corrosion resistance.

Final inspection and trimming:

The finished stainless steel seamless pipe undergoes final inspection, including inspection of outer diameter, wall thickness, inner diameter, and testing of various mechanical properties and chemical composition. Trimming is required to ensure the pipe meets specifications.

Packaging and shipping:

The final stainless steel seamless pipe is packed and ready to ship. Packaging usually involves oiling to prevent rust and then packing in packing materials.