Production Process and Application of 304 Stainless Steel Seamless Bright Tube

Seamless sanitary steel pipe differs from BA-grade seamless steel pipe in several ways, primarily in the following areas:

1. Stainless Steel Pipe Production Process

- Seamless sanitary steel pipe: Typically produced using cold drawing or cold rolling, using high-quality stainless steel ingots or continuous casting billets as raw material. After piercing and rolling, it undergoes degreasing, flattening, and internal and external polishing. Some products may also undergo pickling, passivation, and solution treatment.

- BA-grade seamless steel pipe: Typically undergoes preliminary processing such as cold drawing, followed by vacuum bright annealing. Some products also undergo mechanical polishing of the internal and external surfaces.

2. Surface Quality of Stainless Steel Pipe

- Seamless sanitary steel pipe: Features a high internal and external surface finish. After polishing, the surface finish can reach Ra 0.2-0.4μm or even higher. The surface is free of oil stains, impurities, scratches, and other defects, meeting the stringent hygiene requirements of industries such as food and pharmaceuticals. - BA Grade Seamless Steel Pipe: The surface is smooth and clean, and the inner surface finish is better than polished. The inner surface finish can generally reach approximately Ra 0.4μm.

3. Dimensional Accuracy of Stainless Steel Pipes

- Seamless Sanitary Steel Pipe: The outer diameter tolerance can reach ±0.05mm, and the wall thickness tolerance can also reach ±0.05mm, sometimes even ±0.03mm. The inner bore size tolerance is strictly controlled, reaching ±0.03mm.

- BA Grade Seamless Steel Pipe: The dimensions are precise, and its accuracy can meet higher requirements, but the specific tolerance values may vary depending on the manufacturer and standard.

4. Applications of Stainless Steel Pipes

- Seamless Sanitary Steel Pipe: Widely used in industries such as food, beverages, beer, pharmaceuticals, biotechnology, and drinking water. These industries have extremely high requirements for pipe hygiene and corrosion resistance to ensure product contamination. - BA-Grade Seamless Steel Pipe: Primarily used in biopharmaceuticals, electronic cleanrooms, high-purity gas processing, high-requirement cleanroom laboratories, liquid crystal displays, solar photovoltaics, and polysilicon, for conveying special gases or liquids.

5. Corrosion Resistance of Stainless Steel Pipes

- Seamless Sanitary Steel Pipe: Through pickling and passivation treatments, a thin, dense, and hard passivation film is formed on the inner and outer walls, providing excellent corrosion resistance, effectively preventing corrosion, and ensuring the purity of the conveyed medium.

- BA-Grade Seamless Steel Pipe: After bright annealing and other treatments, it also exhibits good corrosion resistance, but in certain special environments, its corrosion resistance may be slightly inferior to that of seamless steel.

6. Appearance Requirements for Stainless Steel Pipes

- Seamless Sanitary Steel Pipe: Generally, the inner and outer surfaces are required to be bright and uniform in color, without significant color differences or defects, to meet both hygienic and aesthetic requirements.

- BA-Grade Seamless Steel Pipe: Appearance requirements are relatively low, emphasizing surface smoothness and cleanliness. Requirements for color uniformity and other aspects are less stringent than for seamless sanitary steel pipe.