CHS 21x1.2 Gerdau · Weight & Dimensions

Gerdau, tubes · Circular Hollow Section

Circular Hollow Sections (CHS) are round tubular profiles with the most efficient cross-section for compression. Used for columns, trusses, and architectural structures.

Also known as: Caño estructural redondo (Argentina)

The CHS 21x1.2 steel profile weighs 0.6 kg/m (0.40 lb/ft). Cross-sectional area: 74.644 mm². Moment of inertia Ix = 0.367 cm⁴, Iy = 0.367 cm⁴.

Cross-section (not to scale)

Gauge equivalent: 1.2 mm ≈ 18 gauge (Manufacturers Standard Gage)

Dimensions

Property	Metric	Imperial
Thickness (t)	1.2 mm	0.05 in
Diameter (d)	21 mm	0.83 in
Weight	0.6 kg/m	0.40 lb/ft

Section Properties

Property	Metric	Imperial
Area (A)	74.64 mm²	0.116 in²
Moment of inertia (Ix)	0.37 cm⁴	0.01 in⁴
Moment of inertia (Iy)	0.37 cm⁴	0.01 in⁴
Elastic section modulus (Sx)	0.35 cm³	0.021 in³
Elastic section modulus (Sy)	0.35 cm³	0.021 in³
Plastic section modulus (Zx)	0.47 cm³	0.029 in³
Plastic section modulus (Zy)	0.47 cm³	0.029 in³
Radius of gyration (rx)	0.7 cm	0.276 in
Radius of gyration (ry)	0.7 cm	0.276 in