Seamless steel pipes feature a hollow cross-section and are extensively used as pipelines for conveying fluids such as oil, gas, water, and certain solid materials. Compared to solid steel products like round bars, seamless steel pipes offer the same bending and torsional strength but with less weight, making them an economical cross-section steel. They are widely employed in the manufacturing of structural components and mechanical parts, such as oil drill pipes, automotive propshafts, bicycle frames, and steel scaffolding for construction work. The use of seamless steel pipes to produce circular parts enhances material utilization, simplifies manufacturing processes, and saves on materials and labor, thus being widely utilized in pipe production.

Production Process

① Main production processes of hot-rolled seamless steel tubes (△Main inspection processes): billet preparation and inspection △→billet heating→piercing→rolling→steel tube reheating→ sizing (reduction) → heat treatment △→finished tube straightening→finishing→inspection △(non-destructive, physical and chemical, desk inspection) → warehousing

② Main production processes of cold-rolled (drawn) seamless steel tubes: billet preparation → acid pickling and lubrication → cold rolling (drawing) → heat treatment → straightening → finishing → inspection

Current Seamless Steel Pipe Standards in China:

1. Current seamless steel tube standards: A total of 47 items, including GB 25 items, HB 3 items, special-purpose 19 items; basic 2 items, product 45 items.

2. Standard Specifications:

GB/T 2102-2006 Steel Tube Acceptance, Packaging, Marking, and Quality Certificate

② Seamless Steel Pipe Dimensions, Shape, Weight, and Allowable Deviations - GB/T 17395-2008

③ Seamless steel tubes for high-pressure boilers, GB 5310-2008.

④ Seamless Steel Tubes for Petroleum Cracking (GB 9948-2013)

⑤ Seamless Steel Pipe for High-Pressure Equipment - GB 6479-2013