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O-ring weight calculation
O-ring weight = volume × material density. The core is to first calculate the ring volume and then multiply by the corresponding material density.
1. Standard calculation formula (mm/g)
1. Volume formula (most commonly used)
Known: inner diameter ID (mm), wire diameter CS (mm), density ρ (g/cm³)
Medium diameter MD = ID + CS
Volume V = π × (CS/2)² × π × MD = π² × CS² × MD / 4 (mm³)
Weight W = V × ρ / 1000 (g)
2. Simplified formulas (commonly used in engineering)
W = 0.002467 × CS² × (ID + CS) × ρ
2. Density reference of common materials (g/cm³)
3. Calculation examples
- ID=50mm，CS=4mm，NBR（ρ=1.2）
- MD=50+4=54mm
- W=0.002467×4²×54×1.2 ≈ 2.56 g / 个
4. Online calculator entrance (direct use)
O-ring weight calculation online simple version
5. Unit conversion (lb/kg)
1 g = 0.00220462 lb
1 kg = 2.20462 lbs
Total weight = unit weight × quantity