Question 1

How do I calculate the weight of a steel plate?

Accepted Answer

Steel plate weight (kg) = Length (m) × Width (m) × Thickness (m) × Density (kg/m³). Mild steel density = 7,850 kg/m³. Example: 2400mm × 1200mm × 10mm plate: Weight = 2.4 × 1.2 × 0.010 × 7850 = 226.1 kg. Standard plate sizes in South Africa: 2400×1200mm, 3000×1500mm, 6000×1500mm, 6000×2000mm. Thickness range: 3mm, 5mm, 6mm, 8mm, 10mm, 12mm, 16mm, 20mm, 25mm.

Question 2

How do I calculate the weight of round bar per metre?

Accepted Answer

Round bar weight per metre (kg/m) = 0.00617 × D² (for mild steel), where D is diameter in mm. This formula comes from: π/4 × D² × 7850/1000000. Examples: 20mm bar = 2.47 kg/m, 50mm bar = 15.4 kg/m, 100mm bar = 61.7 kg/m. SANS 657 specifies standard diameters: 6, 8, 10, 12, 16, 20, 25, 32, 40, 50, 60, 80, 100mm.

Question 3

How do I calculate hollow pipe or tube weight?

Accepted Answer

Pipe weight (kg/m) = π × (OD - t) × t × density, where OD is outer diameter (m) and t is wall thickness (m). Simplified: kg/m = π × (D/2 - t/2)² × density (for full, then subtract hollow). Per SANS 719 and 657: CHS 60.3×3.2mm = 4.51 kg/m. Pipe dimensions follow DN (nominal bore) sizes. Example: 88.9×4.0mm pipe = 8.38 kg/m.

Question 4

What does RHS and SHS stand for in structural steel?

Accepted Answer

RHS = Rectangular Hollow Section. SHS = Square Hollow Section (a special case of RHS where width = height). Both are specified per SANS 657-2 / ASTM A500. Weight formula: Mass/m = 2 × t × (H + W - 2t) × density, where H = height, W = width, t = wall thickness. Example: 100×50×4mm RHS ≈ 6.71 kg/m. Standard lengths: 6m, 9m, 12m. Available in grades S235JR, S275JR, S355JR.

Question 5

How do I calculate the weight of angle iron (L-section)?

Accepted Answer

Equal angle weight/m = t × (2L - t) × density, where L = leg width, t = leg thickness. For unequal angle (A × B × t): weight/m = t × (A + B - t) × density. Example: 75×75×8mm equal angle = 8.96 kg/m. SANS 657 stock sizes range from 25×25×3mm (1.12 kg/m) to 200×200×25mm (73.7 kg/m). Angles are used for frames, supports, brackets, and connections.

Question 6

What is the density of mild steel vs stainless steel?

Accepted Answer

Material densities (kg/m³): Mild steel / carbon steel: 7,850. Stainless steel 304/316: 7,930. Stainless steel 430: 7,700. Aluminium 6061: 2,700. Copper: 8,960. Cast iron: 7,200. Brass: 8,530. The 7.85 rule for mild steel comes from the standard density of 7850 kg/m³. Using the correct density is critical for cost estimates, structural load calculations, and shipping weight.

Question 7

How many kg does a standard 6m mild steel bar cost?

Accepted Answer

Steel pricing is typically per kilogram or per length. To calculate total weight: quantity × mass/metre × length. Example: 10 lengths of 50mm round bar × 6m = 10 × 15.4 kg/m × 6m = 924 kg. At R12/kg this = R11,088. Standard steel lengths: 6m (most common), 9m, 12m. Some sections available in 3m offcuts. Get current pricing from ManufacturingEzyFind suppliers for accurate quotes.

Question 8

What steel sections are available in South Africa (SANS standards)?

Accepted Answer

South African structural steel standards: SANS 50025 (structural steel grades). SANS 657-1: Hot-rolled bars, rods, flats. SANS 657-2: Steel tubes (hollow sections). SANS 719: Electric welded structural steel tubes. IPE beams: IPE100 to IPE600. HEA/HEB columns: 100mm to 1000mm. PFC channels: 75×40 to 380×100mm. Grades: S235JR, S275JR, S355JR. ARMCO supplies most standard sections; L&K Weston distributes nationally.

Steel Weight Calculator

Steel / Metal Weight Calculator

Find Steel Suppliers

Quick Reference (kg/m)

Frequently Asked Questions

Related Engineering Calculators

Pipe Flow Calculator

Welding Heat Input

Beam Load Calculator

Thermal Expansion

Ready to Source Your Steel?