Industrial Seamless Steel Pipes Cold Rolled Drawn Dom Stainless Ss Carbon Alloy Building Material

Key Features:

• Smaller outside diameter.
• High precision suitable for small batch production.
• Cold-drawn finished products offer high precision and superior surface quality.
• Dense metal structure with superior performance.

Manufacturing Methods:

Production methods include hot rolled, cold rolled, cold drawn, and extruded pipes. Hot-rolled seamless pipes are typically produced on automatic rolling mills. For smaller sizes and better quality, cold rolling or cold drawing is adopted. Extrusion is used for pipes with very small diameters by forcing heated metal through a die.

The "Four Fires" of heat treatment include:

• Annealing: Heating and slow cooling to reach equilibrium and improve service properties.
• Normalizing: Air cooling after heating to refine microstructure and improve cutting performance.
• Quenching: Rapid cooling in water or oil to increase hardness.
• Tempering: Heating after quenching to reduce brittleness and improve toughness.

Hot-rolled Pipe: Outer diameter 32~630mm, Wall thickness 2.5~75mm.

Cold-rolled/Drawn Pipe: Outer diameter 5~200mm, Wall thickness 2.5~12mm.

Quality Standard: Internal and external surfaces must be free of cracks, folds, and scabs. Ends are cut at right angles with burrs removed.

Seamless pipes are widely used for conveying fluids and as structural parts. Key applications include:

• Pipeline transport for water and natural gas.
• Boiler pipes and hydraulic systems.
• Automobile and machinery industries.
• Geological and petroleum drilling projects.