En24 Round Bar Weight Calculator

Accurately estimate the weight and cost potential of High Tensile Steel Engineering Bars

Weight Per Bar

0.00 kg

Volume Per Bar

0.00 cm³

Steel Grade

EN24 (7.85 g/cm³)

Calculation Logic: Weight = π × (Radius)² × Length × Density
Based on EN24 density of 7850 kg/m³.

Figure 1: Weight comparison of EN24 vs Aluminum and Stainless Steel for the specified dimensions.

What is an EN24 Round Bar Weight Calculator?

An EN24 round bar weight calculator is a specialized digital tool designed for engineers, fabricators, and procurement specialists working with EN24 high-tensile steel. EN24 (also known as 817M40) is a high-quality alloy steel often supplied in the "T" condition, offering excellent combination of tensile strength, shock resistance, and ductility.

Unlike generic metal calculators, this tool is calibrated specifically for the density of EN24 steel (approximately 7.85 g/cm³ or 7850 kg/m³). It helps users determine the logistical requirements, shipping costs, and material handling needs for specific lengths and diameters of round bars before purchasing.

Who should use this tool?

• Machinists: To estimate raw material weight before machining.
• Logistics Managers: To calculate total batch weights for shipping restrictions.
• Design Engineers: To verify component mass for mechanical systems.

EN24 Round Bar Weight Formula and Mathematical Explanation

The calculation relies on geometric volume multiplied by the specific density of the material. Since EN24 is typically supplied as a solid cylinder (round bar), the formula uses the geometry of a cylinder.

The core formula is:

Weight (kg) = Volume (m³) × Density (kg/m³)

Broken down into steps:

1. Calculate Radius: Divide the diameter by 2.
2. Calculate Cross-Sectional Area: Area = π × r²
3. Calculate Volume: Volume = Area × Length
4. Apply Density: Multiply Volume by 7850 (Density of EN24 in kg/m³)

Variables Table

Table 1: Key variables used in the EN24 weight calculation logic.

Variable	Meaning	Unit Used in Formula	Typical Range
r	Radius of the bar	Meters (m)	0.005m – 0.25m
L	Length of the bar	Meters (m)	0.1m – 6.0m
ρ (rho)	Density of EN24	kg/m³	Fixed at ~7850
π	Pi Constant	Dimensionless	~3.14159

Practical Examples (Real-World Use Cases)

Example 1: Manufacturing a Gear Shaft

An engineer needs to manufacture a gear shaft using a 50mm diameter EN24 bar that is 500mm long.

• Input Diameter: 50 mm (0.05 m)
• Input Length: 500 mm (0.5 m)
• Radius: 0.025 m
• Volume: π × 0.025² × 0.5 ≈ 0.0009817 m³
• Weight Calculation: 0.0009817 × 7850 ≈ 7.71 kg

Interpretation: The raw slug weighs 7.71 kg. If the final machined part weighs 5.0 kg, then 2.71 kg of material will be removed as swarf (chips).

Example 2: Bulk Ordering for Inventory

A workshop is ordering stock for inventory: 10 bars of 100mm diameter, each 2 meters (2000mm) long.

• Single Bar Volume: π × 0.05² × 2 ≈ 0.015708 m³
• Single Bar Weight: 0.015708 × 7850 ≈ 123.31 kg
• Total Batch Weight: 123.31 kg × 10 = 1,233.1 kg

Financial Interpretation: The shipment exceeds 1 tonne, likely requiring a heavy-goods vehicle for delivery and a forklift rated for 1.5 tonnes to unload safely.

How to Use This EN24 Round Bar Weight Calculator

1. Enter Diameter: Input the cross-sectional diameter in millimeters (mm). This is the "thickness" of the bar.
2. Enter Length: Input the total length of the piece in millimeters. For 1 meter, enter 1000.
3. Set Quantity: If you are calculating a batch, enter the number of pieces. Default is 1.
4. Review Results: The calculator instantly updates the total weight, single bar weight, and volume.
5. Analyze the Chart: Use the visual graph to compare the EN24 weight against other common materials like Aluminum to understand relative heaviness.
6. Copy Data: Use the "Copy Results" button to paste the data into your procurement spreadsheets or emails.

Key Factors That Affect EN24 Weight Results

While the formula provides a theoretical weight, several real-world factors can influence the actual weight of the steel delivered.

1. Manufacturing Tolerances

EN24 bars are manufactured to specific tolerances (e.g., h9, k11). A bar nominally sold as "50mm" might actually be 50.05mm or 49.95mm. On large batches, these micron-level deviations can add up to measurable weight differences.

2. Alloy Composition Density Variations

EN24 is an alloy containing Nickel, Chromium, and Molybdenum. Slight variations in the percentage of these heavy elements within the allowable standard (BS 970) can cause the density to fluctuate slightly between 7840 and 7860 kg/m³.

3. Surface Scale and Finish

"Black bar" EN24 (hot rolled) often has a rough, scaly surface layer which may add slight volume/weight compared to "Bright bar" (peeled or drawn) which is smooth. The calculator assumes a clean geometric cylinder.

4. Temperature Expansion

Steel expands when hot. If you measure volume at high temperatures but calculate weight based on room-temperature density, discrepancies may occur. Standard calculations assume 20°C.

5. End Cuts and Saw Kerf

If you are calculating weight based on cutting a long bar into shorter pieces, remember to account for material lost to the saw blade (kerf), which reduces the total usable weight.

6. Packaging Materials

For logistics, the "gross weight" will be higher than the "net weight" calculated here. Wooden pallets, plastic wrapping, and steel banding can add 20-50kg per pallet.

Frequently Asked Questions (FAQ)

What is the density of EN24 steel?

The typical density of EN24 steel is 7.85 g/cm³ or 7850 kg/m³. This is very similar to other low-alloy steels but denser than stainless steel 304 (approx 7.9 g/cm³).

Can I use this calculator for other steel grades?

Yes, but with a caveat. Most carbon and alloy steels (like EN8, EN19, Mild Steel) have a density very close to 7850 kg/m³, so the result will be accurate within 1-2%. Do not use it for Aluminum or Titanium.

Does EN24 weigh more than Stainless Steel?

Generally, no. Austenitic stainless steels like 304 or 316 have a slightly higher density (approx 7900-8000 kg/m³) due to higher Nickel and Chromium content. EN24 is slightly lighter per unit volume.

Why is the weight in kilograms?

The metric system is the global standard for engineering materials. However, 1 kg is approximately 2.20462 lbs if you need to convert for imperial applications.

Is EN24 magnetic?

Yes, EN24 is a ferromagnetic material. This property is useful for magnetic lifting during transport, which relies on the weight limits calculated here.

How accurate is the theoretical weight?

Theoretical weight is usually within +/- 2% of actual scale weight. Variations arise from dimensional tolerances and specific alloy chemistry heats.

What is the difference between EN24 and EN24T?

EN24 is the grade, while "T" refers to the heat treatment condition (Tensile strength 850-1000 MPa). The density and weight remain the same regardless of the heat treatment condition.

How do I calculate the cost from the weight?

Multiply the Total Weight (kg) by your supplier's price per kg. For example, if EN24 is $3.50/kg and your bar weighs 10kg, the material cost is $35.00.

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