Calculate the exact weight of Square Bars in Mild Steel (MS), Stainless Steel (SS), EN8, Copper, and Brass instantly with our free online calculator. Simply enter your side dimension and length in mm or inches, and get accurate results in both kg and lbs.
Weight Calculation for Square Bar
The weight of a Square Bar (also known as Solid Square Stock) is determined by its cross-sectional area, length, and material density. Unlike hollow sections, square bars are solid throughout, making them essential for machining shafts, keyways, structural supports, and decorative metalwork. The standard density for Mild Steel is 7.85 g/cm³, while other engineering materials like EN8, Stainless Steel, Copper, and Brass have distinct densities that significantly affect the final weight. Accurate weight calculation is critical for material procurement, logistics planning, and precise cost estimation in engineering and fabrication projects.
Square Bar Weight Formula and Manual Calculation
The industry-standard formula for calculating square bar weight is based on the volume of a rectangular prism:
Weight (kg) = Side² (mm) × Length (m) × Density Factor
Density Factors for common materials:
0.00000785 for Mild Steel (MS) & EN8 Steel
0.00000793 for Stainless Steel (SS 304/316)
0.00000850 for Brass
0.00000896 for Copper
0.00000270 for Aluminium
For imperial units (inches and lbs):
Weight (lbs) = Side² (in) × Length (ft) × 3.4 (for Steel)
Step-by-Step Calculation Example
- Step 1: Identify dimensions: Side = 20 mm, Length = 3 m (Mild Steel)
- Step 2: Calculate Cross-Sectional Area: 20 × 20 = 400 mm²
- Step 3: Apply formula: 400 × 3 × 0.00000785
- Step 4: Result: 1200 × 0.00000785 = 9.42 kg
- Step 5: Compare with Brass: 9.42 × (8.50/7.85) ≈ 10.20 kg
This calculation aligns exactly with the results provided by the MS square bar weight calculator in kg.
Metal Square Bar Weight Chart (Quick Reference per Metre)
Frequently Asked Questions
What is the difference between EN8 and Mild Steel square bars?
EN8 is a medium carbon steel with higher tensile strength and hardness compared to standard Mild Steel (MS). While their densities are nearly identical (approx. 7.85 g/cm³), EN8 is preferred for high-stress applications like gears and shafts, whereas MS is used for general structural fabrication. The weight calculation remains the same for both.
How do I calculate the weight of a Brass square bar?
To calculate the weight of a Brass square bar, use the formula: Side² (mm) × Length (m) × 0.00000850. Brass is denser than steel, so a brass bar of the same size will weigh approximately 8% more than a mild steel bar.
What is the unit weight of a 20mm MS square bar?
A standard 20mm Mild Steel square bar has a unit weight of approximately 3.14 kg per metre. This is calculated as: 20 × 20 × 0.00000785 = 3.14 kg. For a 3-metre length, the total weight would be 9.42 kg.