In modern structural engineering and metal fabrication, hollow extruded sections represent the supreme balance of geometric moment of inertia and minimum metal mass. When comparing load resistance per kilogram, hollow aluminium tubes drastically outperform solid rods and heavy mild steel angles.
From high-rise architectural stair balustrades, solar panel ground-mount frameworks, and modular cleanroom wall systems to commercial vehicle bus body construction, aluminium square tubes and seamless round pipes extruded by Jindal Aluminium are the primary building blocks of Indian industrial manufacturing.
However, fabricators and site contractors frequently struggle to select the correct combination of profile geometry, wall gauge thickness, and heat-treated alloy temper. In this practical technical guide, Imperial Metal Mart provides complete dimensional charts, weight tables, and fabrication best practices.
The 3 Primary Hollow Profile Geometries
Each geometric form possesses unique torsional, bending, and hydrodynamic properties suited for designated fabrication functions:
1. Square Hollow Sections (SHS)
Features equal moments of inertia along both principal axes (Ix = Iy). This symmetrical rigidity prevents buckling under multi-directional compressive column loads.
Primary Uses:Structural upright posts, equipment support frames, modular display racks, cleanroom partitions. Standard sizes: 19x19mm (0.75") up to 100x100mm (4").
2. Rectangular Hollow Sections (RHS / Box Sections)
Engineered with a deeper primary vertical axis, providing maximum resistance against downward bending deflection under span loads.
Primary Uses:Horizontal roof purlins, pergola rafters, bus body flooring subframes, partition perimeter frames. Standard sizes: 50x25mm (2"x1"), 75x38mm, 100x50mm (4"x2").
3. Extruded Round Pipes & Tubes
Round geometry offers zero drag, superior aerodynamic fluid flow, and uniform torsional resistance in all radial directions.
Primary Uses:Architectural handrails, industrial scaffolding poles, heat exchanger tubes, irrigation pipes, bicycle frames. Standard sizes: 12.7mm (0.5") OD up to 150mm+ OD.
Standard Sizes, Gauges & Theoretical Weight Reference Table
Below is a master reference chart of popular Jindal Aluminium square and round profile dimensions widely stocked across Delhi NCR, detailing wall thickness and weight:
| Section Type & Outer Dimension | Wall Gauge (mm) | Weight (kg / meter) | Weight (kg / 12ft Length) | Typical Application |
|---|---|---|---|---|
| Square Tube: 25.4 × 25.4 mm (1" × 1") | 1.20 mm | 0.315 kg/m | 1.15 kg | Light framing, display racks |
| Square Tube: 38.1 × 38.1 mm (1.5" × 1.5") | 1.50 mm | 0.595 kg/m | 2.18 kg | Furniture, partition studs |
| Square Tube: 50.8 × 50.8 mm (2" × 2") | 2.00 mm | 1.055 kg/m | 3.86 kg | Pergola posts, gate framing |
| Rectangular Tube: 50.8 × 25.4 mm (2" × 1") | 1.50 mm | 0.595 kg/m | 2.18 kg | Louvers, signboards, railings |
| Rectangular Tube: 101.6 × 50.8 mm (4" × 2") | 2.50 mm | 1.990 kg/m | 7.28 kg | Heavy structural roof beams |
| Round Pipe: 25.4 mm OD (1" OD) | 1.50 mm | 0.304 kg/m | 1.11 kg | Curtain rods, interior rails |
| Round Pipe: 50.8 mm OD (2" OD) | 2.00 mm | 0.828 kg/m | 3.03 kg | Handrails, balustrades, poles |
| Heavy Round Pipe: 60.3 mm OD (2.37" OD) | 3.20 mm | 1.550 kg/m | 5.67 kg | Scaffolding, fluid piping |
Choosing Between Alloy 6063-T6 and 6061-T6 for Tubing
When purchasing structural tubes, selecting the right alloy prevents unexpected mechanical failures or poor finishing results:
- Specify Alloy 6063-T6 If: You are constructing architectural handrails, window frames, interior partitions, or decorative outdoor pergolas where surface finish, crisp aesthetics, and anodizing quality are paramount. 6063-T6 delivers a yield strength of ~214 MPa and mirror-smooth surfaces ready for high-gloss powder coating.
- Specify Alloy 6061-T6 / 6082-T6 If: You are fabricating heavy load-bearing structural assemblies, industrial scaffolding, truck trailers, or solar mounting structures where high tensile yield strength (~276 MPa, almost 30% higher) is required to resist wind loads and dynamic mechanical shock.
Fabrication Guidelines: Cutting, Bending & Welding
Aluminium requires different workshop fabrication techniques compared to carbon steel:
- High-Speed Carbide Saws: Cut tubes using dedicated non-ferrous carbide-tipped circular saw blades (80 to 100 teeth) running at high RPM (3,000+ RPM) with light ethanol or wax mist lubrication to achieve burr-free square cuts.
- Rotary Draw Mandrel Bending: When bending thin-walled round tubes for curved handrails or canopies, always use internal steel mandrels or packed dry silica sand inside the pipe cavity to prevent wall collapse and throat wrinkling.
- TIG (GTAW) & MIG (GMAW) Welding: Thoroughly remove the oxide film using a stainless steel dedicated wire brush immediately before welding. Use 100% pure Argon shielding gas and ER4043 or ER5356 filler wire.
Frequently Asked Questions
Are aluminium round pipes seamless?
Yes. Extruded aluminium pipes manufactured by Jindal Aluminium are seamless profiles pushed continuously through hardened extrusion dies over a central mandrel. They have zero longitudinal weld seams, offering uniform burst pressure strength and continuous circular wall thickness.
How can I check if a tube has been under-gauged?
Use a digital micrometer or vernier caliper to measure wall thickness at four points around the perimeter. Next, weigh the entire 12ft piece on a digital scale and divide by 3.66 meters. Compare the result with the official Jindal weight chart. A deviation greater than ±5% to 7% signals fraudulent under-gauging.
Can aluminium tubes be powder coated in wood finish?
Yes. Square and rectangular aluminium tubes are frequently finished with wood grain sublimation, giving them the rich texture of natural teak, walnut, or oak while retaining all the structural strength, termite immunity, and fire-resistance of aluminium.
Source Certified Aluminium Tubes & Pipes in Delhi NCR
Imperial Metal Mart maintains ready stock of square, rectangular, and round extruded aluminium tubes in standard 12-foot and 15-foot lengths in Mill Finish, Anodized, and Powder Coated finishes.