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Tube & Structural Tube

Tube & Structural Tube

Round, square and rectangular tube in steel, aluminum and stainless.

Also searched as: square tuberound tubedom tubestructural tubebox section

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About tube & structural tube

Tube and structural tube are hollow profiles utilized in construction, mechanical assemblies, and architectural applications for their strength-to-weight ratio and rigidity. This category encompasses round, square, and rectangular cross-sections, primarily manufactured from steel (including mild steel, DOM, and various alloys), aluminum (e.g., 6061-T6, 6063-T5), and stainless steel (e.g., 304, 316). Key selection parameters include outside diameter (OD) or side dimensions, wall thickness (gauge), and overall length. Steel tubing often conforms to standards such as ASTM A500 for cold-formed welded and seamless carbon steel structural tubing, or ASTM A513 for electric-resistance-welded carbon and alloy steel mechanical tubing. Aluminum tubing frequently adheres to ASTM B221 or B429. Surface finishes vary from mill finish to galvanized, painted, or anodized, depending on corrosion resistance and aesthetic requirements. DOM (Drawn Over Mandrel) tubing is characterized by its superior concentricity, dimensional accuracy, and smooth internal and external surfaces, making it suitable for hydraulic cylinders and precision shafts. Structural tube, often referred to as box section, is designed for load-bearing applications where high strength and torsional rigidity are critical.

How to choose

Selecting the appropriate tube begins with defining the application's structural requirements. First, determine the necessary cross-sectional shape: round for fluid transfer or aesthetics, square/rectangular for structural framing and torsional rigidity. Second, specify the material based on strength, weight, and environmental exposure; steel offers high strength, aluminum provides a lighter alternative, and stainless steel ensures corrosion resistance. Third, calculate the required outer dimensions (OD for round, side length for square/rectangular) and wall thickness to meet load-bearing and deflection criteria. Thicker walls increase strength but also weight and cost. Finally, consider the manufacturing process (e.g., seamless for pressure, DOM for precision) and any required surface finishes for environmental protection or appearance.