Product Overview
Square tube starts as strip that is roll formed and high frequency welded, then sized and squared. The corners carry a radius, the outside face is flat and the internal weld flash is scarfed off, so there are no sharp internal stress raisers. For the same cross sectional area a square hollow section is stiffer in torsion and in-plane bending than a round tube, and its flat faces make bolting and panel fixing simple – the reason it dominates trusses, curtain wall mullions and handrails.
Specifications
| Parameter | Value |
|---|---|
| Size range | 20x20x1.5 to 200x200x8 mm |
| Common sizes | 20×20 / 40×40 / 60×60 / 100×100 mm |
| Wall thickness | 1.5 – 6.0 mm |
| Steel grade | Q235B / S235JR / A500 Gr.B |
| Yield strength | min 235 MPa |
| Tensile strength | 375 – 500 MPa |
| Corner radius | 1.5 – 3.0 x wall thickness |
| Wall tolerance | +/- 10% |
| Standard length | 6 m / 9 m / 12 m |
| Weld | High frequency / internal flash removed |
Applications
Used for factory trusses and column bracing, glass and aluminium curtain wall mullions, racking uprights, machine guard rails, solar mounting frames, bus shelter frames and handrail posts. Curtain wall contractors in the Middle East and steel fabricators in Africa usually order cut to drawing length with square cuts for easy assembly.
Packing / Delivery / Payment
Packed bare in hexagonal or square bundles of 1-3 tons with timber dunnage and end protection; a 20GP holds about 25 tons. Stock ships in 7-15 days, rolling orders in 20-25 days, and galvanizing adds 10-15 days. Payment by L/C at sight or T/T with 30% deposit. EN 10204 3.1 mill certificate, weld inspection report, packing list and Certificate of Origin are provided.