ISMB 350 weight and dimensions

52.33 kg/m · 35.16 lb/ft

ISMB 350 is a 350 mm deep beam with a 140 mm flange, 8.1 mm web and 14.2 mm flange thickness. It weighs 52.33 kg per metre (35.16 lb/ft). It belongs to the ISMB medium weight beam series, Indian Standard (IS 808).

ISMB 350 weight calculator

Total weight
—

Weight of standard lengths

Pieces6 m each (kg)12 m each (kg)
1314.0628.0
51,569.93,139.8
103,139.86,279.6
206,279.612,559.2
5015,699.031,398.0

Pieces per tonne

6 m lengths per metric tonne3.2
12 m lengths per metric tonne1.6
Length per tonne19.1 m

Useful for converting a tonnage order into a number of bars.

Surface area for painting

Per metre of length1.220 m²/m
Per foot of length4.00 ft²/ft
Per tonne of steel23.3 m²/t
A 12 m length14.64 m²

Outside perimeter × length, all faces, calculated from the dimensions. Use it to estimate paint, primer, fireproofing or galvanizing quantities.

Cross-section

ISMB 350 cross-section, drawn to scaleh 350b 140tw 8.1tf 14.2r 14

Drawn to scale. Dimensions in mm.

Dimensions

Depth h 350 mm 13.780 in
Flange width b 140 mm 5.512 in
Web thickness tw 8.1 mm 0.319 in
Flange thickness tf 14.2 mm 0.559 in
Root radius r 14 mm 0.551 in
Toe radius r2 7 mm 0.276 in
Flange slope (deg) 98°
Mass52.33 kg/m35.16 lb/ft

Section properties

PropertyValueUnit
Area66.70cm²
Moment of inertia Ix13,600cm⁴
Moment of inertia Iy537cm⁴
Elastic modulus Zx779cm³
Elastic modulus Zy76.80cm³
Plastic modulus Zpx889cm³
Plastic modulus Zpy129cm³
Radius of gyration rx14.20cm
Radius of gyration ry2.83cm
Torsion constant J43.10cm⁴

Equivalent sections in other standards

The closest sections by depth and weight. They are not direct substitutes: check bending, buckling and connection details before swapping one for another.

Overlay of ISMB 350, IPE 360, IPE 330, W14x34, drawn to the same scaleISMB 350IPE 360IPE 330W14x34ISMB 350 — 52.33 kg/mIPE 360 — 57.09 kg/mIPE 330 — 49.15 kg/mW14x34 — 51 kg/m

ISMB 350 and its closest equivalents, drawn over each other at the same scale.

SectionStandardDepth (mm)kg/mWeight vs ISMB 350
ISMB 350IS35052.33—
IPE 360 EN 360 57.09 +9.1%
IPE 330 EN 330 49.15 -6.1%
W14x34 AISC 356 51.00 -2.5%
W14x38 AISC 358 57.80 +10.5%

ISMB series weights

061121 ISMB 100: 8.95 kg/m 100 ISMB 125: 13.35 kg/m 125 ISMB 150: 14.96 kg/m 150 ISMB 175: 19.5 kg/m 175 ISMB 200: 24.17 kg/m 200 ISMB 225: 31.15 kg/m 225 ISMB 250: 37.3 kg/m 250 ISMB 300: 46.02 kg/m 300 ISMB 350: 52.33 kg/m 350 ISMB 400: 61.55 kg/m 400 ISMB 450: 72.38 kg/m 450 ISMB 500: 86.88 kg/m 500 ISMB 550: 103.64 kg/m 550 ISMB 600: 121 kg/m 600 kg/m

Next lighter: ISMB 300 (46.02 kg/m). Next heavier: ISMB 400 (61.55 kg/m).

Stiffness and strength per kilogram

The elastic section modulus Zx governs bending strength. Dividing it by the weight shows how efficiently each size uses its steel: higher is better when weight is the cost driver.

Sectionkg/mIx (cm⁴)Zx (cm³)Zx per kg/m
ISMB 225 31.153,440306.0 9.82
ISMB 250 37.305,130410.0 10.99
ISMB 300 46.028,990599.0 13.02
ISMB 350 52.3313,600779.0 14.89
ISMB 400 61.5520,4001,020.0 16.57
ISMB 450 72.3830,4001,350.0 18.65
ISMB 500 86.8845,2001,800.0 20.72

Full table: ISMB weight chart (PDF).

How the weight is calculated

Mass per metre = cross-sectional area × density of steel = 66.70 cm² × 0.785 kg/(cm²·m) = 52.36 kg/m.

Rolled sections are made to a nominal mass, and the actual mass can differ by a few percent within the tolerances of IS 1852. For purchasing, invoicing by weight or checking deliveries, use the producer's stated mass.

Typical uses

Beams of this shape are used as floor and roof beams, lintels, crane girders and frame members, where bending about the strong axis governs.

Steel I-beams being erected as bridge girders over a highway
Photo: MassDOT, Wikimedia Commons, public domain.

Frequently asked questions

What is the weight of ISMB 350 per metre?

ISMB 350 weighs 52.33 kg/m, which is 35.16 lb/ft.

How much does a 6 m or 12 m length of ISMB 350 weigh?

A 6 m length weighs about 314.0 kg and a 12 m length about 628.0 kg.

What is the equivalent of ISMB 350 in other standards?

By depth and weight the closest match is IPE 360 (57.09 kg/m, 360 mm deep). Check section properties before substituting one for the other.

Source: IS 808:2021; earlier values from IS 808:1989 and SP 6(1):1964. Values are nominal; verify with the producer before ordering.