Enter current market price to estimate total cost.
Total Weight
0.00 kg
Formula: Volume × Density
Unit Weight
0.00 kg
Total Volume
0.00 cm³
Estimated Cost
$0.00
Weight Breakdown & Comparison
Material
Density (g/cm³)
Total Weight (kg)
Difference
What is a Duplex Weight Calculator?
A duplex weight calculator is a specialized engineering tool designed to estimate the mass of components made from Duplex Stainless Steel (DSS). Unlike standard austenitic stainless steels (like 304 or 316), Duplex steels have a mixed microstructure of austenite and ferrite, resulting in slightly different density characteristics.
This tool is essential for procurement managers, structural engineers, and logistics coordinators who deal with grades like 2205 (Standard Duplex), 2507 (Super Duplex), and 2304 (Lean Duplex). Accurate weight calculation ensures precise shipping cost estimation, structural load planning, and material purchasing budgets.
Common misconceptions include assuming all stainless steel has the same density. While 304 stainless steel has a density of roughly 7.9 g/cm³, Duplex grades typically range from 7.80 to 7.85 g/cm³. While this difference seems small, it scales significantly across large piping projects or heavy plate orders.
Duplex Weight Formula and Mathematical Explanation
The core principle behind the duplex weight calculator is the relationship between volume and density. The general formula is:
Weight (kg) = Volume (mm³) × Density (g/cm³) / 1,000,000
1. Plate / Sheet Formula
For flat plates, the volume is simply length × width × thickness.
Weight = L × W × T × ρ
2. Round Bar Formula
For solid round bars, we calculate the area of the circle and multiply by length.
Weight = π × (Diameter / 2)² × Length × ρ
3. Pipe / Tube Formula
For hollow pipes, we calculate the volume of the cylinder wall.
Select Material Grade: Choose between Standard 2205, Super Duplex 2507, or Lean Duplex. This sets the correct density automatically.
Choose Shape: Select Plate, Round Bar, or Pipe depending on your component.
Enter Dimensions: Input the measurements in millimeters (mm). Ensure accuracy for OD and Wall Thickness for pipes.
Set Quantity: Enter the number of pieces required.
Input Cost (Optional): If you know the price per kg, enter it to get a total cost estimate.
Review Results: The calculator updates instantly. Use the "Copy Results" button to save the data for your purchase order or report.
Key Factors That Affect Duplex Weight Results
Density Variations: Different Duplex grades have slight density variations due to their chemical composition (Molybdenum and Nitrogen content). 2507 is slightly heavier than 2205.
Dimensional Tolerances: Manufacturing tolerances (ASTM A480 / A789) mean the actual thickness may vary slightly from the nominal thickness, affecting the actual weight by ±5%.
Corner Radius: For rectangular bars or plates, this calculator assumes sharp corners. Rounded corners (common in flat bars) would slightly reduce the weight.
Weld Seams: For welded pipes, the weld reinforcement might add a negligible amount of weight not accounted for in standard theoretical formulas.
Surface Finish: Rough or machined surfaces do not significantly impact weight, but coatings or cladding would add extra mass.
Cost Fluctuations: While weight is constant, the financial result depends on the volatile surcharge for Nickel and Molybdenum.
Frequently Asked Questions (FAQ)
What is the density of Duplex 2205?
The typical density of Duplex 2205 (UNS S31803/S32205) is 7.80 g/cm³ (7800 kg/m³).
Is Duplex steel heavier than 316 stainless steel?
No, Duplex steel is actually slightly lighter. 316 Stainless Steel has a density of roughly 7.98 g/cm³, while Duplex is around 7.80 g/cm³. This means Duplex is about 2% lighter for the same volume.
Can I use this calculator for Super Duplex?
Yes, simply select "Super Duplex 2507" from the dropdown menu. The calculator adjusts the density to 7.81 g/cm³ automatically.
Why do I need to calculate weight for pipes?
Pipe weight calculation is critical for designing pipe supports, estimating shipping costs, and calculating the total material cost, which is often priced per kilogram.
Does this calculator account for packaging weight?
No, this calculator provides the theoretical net weight of the metal itself. You should add 1-3% for wooden crates or pallets for shipping estimates.
What is the formula for pipe weight?
Weight = (OD – Wall Thickness) × Wall Thickness × 0.02466 × Length (m) (for Carbon steel). For Duplex, we use the specific density formula derived in the article above.
How accurate is this calculator?
It provides a theoretical weight based on nominal dimensions. Actual weight may vary due to manufacturing tolerances defined in ASTM standards.
What is Lean Duplex?
Lean Duplex (e.g., 2304) has lower nickel content and a density of approximately 7.80 g/cm³. It is a cost-effective alternative for applications requiring high strength but moderate corrosion resistance.