Calculate the exact weight of Steel Rings, Washers, and Flanges instantly with our free online calculator. Simply enter your outer diameter, inner diameter, and thickness in mm or inches, and get accurate results in both kg and lbs.

Weight Calculation for Ring and Washer

The weight of a Ring or Washer (also known as a Plain Washer) is determined by its volume, which is calculated by subtracting the area of the inner hole from the total outer area. These components are essential in fastening systems, piping flanges, and structural connections. The standard density for mild steel is 7.85 g/cm³. Accurate weight calculation is vital for bulk procurement, shipping estimates, and inventory management.

Ring Weight Formula and Manual Calculation

The industry-standard formula for calculating ring or washer weight is:

Weight (kg) = π × [(Outer Radius)² - (Inner Radius)²] × Thickness (mm) × 0.00000785

Simplified for direct diameter input:

Weight (kg) = (OD² - ID²) × Thickness (mm) × 0.000006165

For imperial units (inches and lbs):

Weight (lbs) = (OD² - ID²) × Thickness (in) × 0.222

Where OD is Outer Diameter, ID is Inner Diameter, and 0.000006165 is the combined constant for pi and steel density when using mm.

Step-by-Step Calculation Example

  • Step 1: Identify dimensions: Outer Diameter (OD) = 100 mm, Inner Diameter (ID) = 50 mm, Thickness = 10 mm
  • Step 2: Calculate Area Difference: (100² - 50²) = 10,000 - 2,500 = 7,500 mm²
  • Step 3: Apply formula: 7,500 × 10 × 0.000006165 = 0.462 kg
  • Step 4: Convert to lbs (optional): 0.462 × 2.20462 ≈ 1.02 lbs

This calculation aligns with the results provided by the steel washer weight calculator.

Steel Washer Weight Chart (Quick Reference)

Size (OD x ID x T) Weight per Piece (kg) Weight per Piece (lbs)
24 x 10 x 2 mm0.006 kg0.013 lbs
50 x 20 x 5 mm0.072 kg0.159 lbs
100 x 50 x 10 mm0.462 kg1.02 lbs
150 x 80 x 15 mm1.85 kg4.08 lbs
200 x 100 x 20 mm4.62 kg10.19 lbs
300 x 150 x 25 mm12.74 kg28.09 lbs

Frequently Asked Questions

How do I calculate the weight of a steel washer?

To calculate the weight of a steel washer, use the formula: Weight = (OD² - ID²) × Thickness × 0.000006165. Ensure all dimensions are in millimetres to obtain the result in kg. This formula accounts for the material removed by the central hole.

What is the difference between a ring and a washer?

Geometrically, a ring and a washer are identical (a disc with a central hole). The term "washer" is typically used for small, thin components used with bolts and nuts, while "ring" is often used for larger structural components, flanges, or jewellery. The weight calculation method remains the same for both.

Can I use this calculator for silver or other metals?

Yes, the geometric formula remains the same, but you must adjust the density factor. For silver (density ~10.49 g/cm³), replace the steel constant 0.000006165 with 0.00000824. Our calculator allows you to select different materials for accurate results.