Accurately calculate the weight and cost of Mild Steel (MS) circles, plates, and discs. Ideal for fabrication estimation, procurement planning, and material cost analysis.
Enter the outer diameter of the MS circle in millimeters.
Please enter a valid positive diameter.
Enter the thickness of the steel plate in millimeters.
Impact of thickness variation on weight (for current diameter)
■ Current Calculation
■ Comparison Values
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What is an MS Circle Weight Calculator?
An MS Circle Weight Calculator is an essential engineering and procurement tool designed to estimate the mass of Mild Steel (MS) circular plates based on their dimensions. Whether you are a fabricator working on flange blanks, a civil engineer planning structural components, or a purchasing manager estimating transport loads, accurate weight calculation is critical for cost control and logistics.
Mild steel is widely used due to its tensile strength and weldability. However, because steel is sold by weight (kg or ton) but used by dimension (mm), converting physical dimensions into weight is a daily requirement in the metal industry. This calculator eliminates manual errors and provides instant results for single pieces and bulk orders.
Who should use this tool?
Fabricators: To estimate material requirements for tank covers, flanges, and base plates.
Estimators: To calculate raw material costs for tenders and quotations.
Logistics Managers: To ensure truck loading does not exceed weight limits.
MS Circle Weight Formula and Explanation
The calculation of MS circle weight relies on the volume of the cylinder formed by the plate and the specific density of Mild Steel. The standard industry density for Mild Steel is approximately 7850 kg/m³ (or 7.85 g/cm³).
The mathematical formula used is:
Weight (kg) = Volume (m³) × Density (kg/m³)
Expanded: Weight = π × r² × t × ρ
Variable Definitions
Variable
Meaning
Unit Used in Formula
Standard Value
π (Pi)
Mathematical Constant
Dimensionless
~3.14159
r (Radius)
Half of Diameter (D/2)
Meters (m)
Variable
t (Thickness)
Plate Thickness
Meters (m)
Variable
ρ (Rho)
Density of Mild Steel
kg/m³
7850
Table 1: Key variables for MS Circle weight calculation.
Practical Examples
Example 1: Standard Base Plate
A fabricator needs a circular base plate for a column. The diameter is 300mm and the thickness is 12mm.
Diameter: 300 mm = 0.3 m (Radius = 0.15 m)
Thickness: 12 mm = 0.012 m
Volume: 3.14159 × 0.15² × 0.012 = 0.0008482 m³
Weight: 0.0008482 × 7850 = 6.66 kg
Example 2: Heavy Machinery Flange Blank
A machine shop requires 10 blanks of 500mm diameter and 25mm thickness. The steel price is 65.00 per kg.
Weight per piece: ~38.53 kg
Total Weight (10 pcs): 385.3 kg
Estimated Cost: 385.3 kg × 65.00 = 25,044.50
How to Use This MS Circle Weight Calculator
Using this tool is straightforward, but accuracy depends on precise inputs. Follow these steps:
Measure Diameter: Enter the outer diameter of your circle in millimeters (mm). Ensure you are measuring the final cut size.
Measure Thickness: Input the plate thickness in mm. Common market thicknesses are 6mm, 8mm, 10mm, 12mm, etc.
Set Quantity: If you are calculating a batch, enter the total number of pieces.
Enter Price (Optional): For financial estimation, input the current market rate per kilogram for Mild Steel.
Review Results: The tool instantly displays the unit weight, total batch weight, and estimated cost.
Key Factors That Affect MS Circle Weight Results
While the math is exact, real-world steel weights can vary. Consider these factors when using the ms circle weight calculator for critical applications:
1. Density Variations
While 7850 kg/m³ is the standard, different grades of mild steel (e.g., IS 2062, A36) may have slight density variations between 7830 and 7870 kg/m³ depending on alloy content.
2. Rolling Tolerance
Steel plates produced in mills have rolling tolerances. A "10mm" plate might actually measure 9.8mm or 10.5mm depending on the manufacturer and standards (e.g., ASTM A6). This can affect actual weight by 3-5%.
3. Cutting Method
When cutting a circle from a square plate using gas or plasma cutting, material is lost as kerf (width of the cut). However, for purchasing, you often pay for the square plate from which the circle is cut. This calculator calculates the net weight of the finished circle, not the gross weight of the raw material.
4. Rust and Scale
Old or stored steel may develop rust or mill scale, which adds negligible weight but may affect thickness measurements if not cleaned before measuring.
5. Coatings and Painting
Galvanizing or painting adds weight. For standard galvanizing, add approximately 3-5% to the calculated black steel weight.
6. Financial Market Fluctuations
The cost calculation is an estimate. Steel prices fluctuate daily based on global ore prices, fuel costs, and local demand. Always confirm rates with suppliers.
Frequently Asked Questions (FAQ)
1. What is the density of Mild Steel used in this calculator?
We use the industry standard density of 7.85 g/cm³ or 7850 kg/m³.
2. Does this calculator apply to Stainless Steel?
No. Stainless steel (SS 304/316) is slightly denser (approx 7.9 – 8.0 g/cm³). Using this MS calculator for SS will result in a slight underestimation of weight.
3. Why is the calculated weight different from the weighbridge ticket?
Weighbridge scales have rounding errors, and actual plate thickness often varies from the nominal size due to rolling tolerances. Always allow for a margin of error of ±2-3%.
4. Can I calculate weight for a hollow ring/washer?
This calculator is for solid circles. For a ring, calculate the weight of the outer circle and subtract the weight of the inner hole circle.
5. How do I convert the weight to tons?
Divide the result in kilograms by 1000. For example, 2500 kg is 2.5 Metric Tons.
6. Does the cost include tax or labor?
No, the "Material Cost" field calculates raw material price only. Labor, cutting charges (burning cost), and taxes (VAT/GST) should be added separately.
7. What is the formula for area of the circle?
Area = π × r². Knowing the area helps in estimating painting or coating requirements.
8. Is this calculator suitable for aluminum circles?
No. Aluminum is much lighter (approx 2.7 g/cm³). Using this tool for aluminum would overestimate weight by nearly 3 times.
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