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Welded steel pipe & tube

Rectangular/ Square hollow section manufacturing process

Rectangular/ Square hollow section are formed from coils and then ran through a series of dies. They are are welded from the inside to form their shape.


Manufacturing flow chart

Measurement the size
They are measured by their outside dimensions and their wall thickness.

Rectangular/ Square hollow section is commonly available in Q195, Q215, Q235, Q345 grade. It can be purchased online and at any Metal Supermarkets location. It can be cut to your exact specifications.

Chemical composition
Steel Grade: Q195, Q215, Q235, Q345, S235JR, S275JR, SS4007-
Data Elements(%)
Materal Grade C Mn S P Si
Q195 0.06-0.12 0.25-0.50 <0.05 <0.045 <0.30
Q215 0.09-0.15 0.25-0.55 <0.05 <0.045 <0.30
Q235 0.12-0.20 0.30-0.70 <0.045 <0.045 <0.30
Q345 <0.20 1.0-1.6 <0.04 <0.04 <0.55
Mechanical property
Materal Grade Yield point (Mpa) Tensile Strength (Mpa) Elongation(%)
Q195 >195 315-430 32-33
Q215 >215 335-450 26-31
Q235 >235 375-500 24-26
Q345 >345 470-630 21-22



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