CHS 21x1.55 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 21x1.55 steel profile weighs 0.7 kg/m (0.50 lb/ft). Cross-sectional area: 94.711 mm². Moment of inertia Ix = 0.451 cm⁴, Iy = 0.451 cm⁴.

Cross-section (not to scale)

Gauge equivalent: 1.55 mm ≈ 16 gauge (Manufacturers Standard Gage)

Dimensions

Property	Metric	Imperial
Thickness (t)	1.6 mm	0.06 in
Diameter (d)	21 mm	0.83 in
Weight	0.7 kg/m	0.50 lb/ft

Section Properties

Property	Metric	Imperial
Area (A)	94.71 mm²	0.147 in²
Moment of inertia (Ix)	0.45 cm⁴	0.01 in⁴
Moment of inertia (Iy)	0.45 cm⁴	0.01 in⁴
Elastic section modulus (Sx)	0.43 cm³	0.026 in³
Elastic section modulus (Sy)	0.43 cm³	0.026 in³
Plastic section modulus (Zx)	0.59 cm³	0.036 in³
Plastic section modulus (Zy)	0.59 cm³	0.036 in³
Radius of gyration (rx)	0.69 cm	0.272 in
Radius of gyration (ry)	0.69 cm	0.272 in