Convert Pound square feet to Tonne square metres
Convert Pound square feet (lb·ft²) to Tonne square metres (t·m²) instantly and accurately.
Conversion Formula
t·m² = lb·ft² × 4.214011009e-5
About Pound square feet
The pound square foot (lb·ft²) equals ≈0.04214 kg·m², the dominant imperial unit for machine and vehicle rotational inertias. Aircraft control-surface counterbalancing, propeller blade inertia, and turbocharger rotor dynamics are specified in lb·ft²; steam turbine discs and helicopter tail-rotor assemblies: 1-10 000 lb·ft². 1 lb·ft² ≈0.04214 kg·m² = 144 lb·in² ≈0.03108 slug·ft².
About Tonne square metres
The tonne square metre (t·m²) equals 1000 kg·m², used for large industrial rotors and heavy rotating machinery. A 60-tonne paper-machine calendar roll of 0.5 m radius has I ≈7.5 t·m²; synchronous hydro-generator rotors: 50-2000 t·m²; large marine propulsion shafts: 5-50 t·m². 1 t·m² = 1000 kg·m² ≈737.6 slug·ft² ≈23 730 lb·ft².
Quick Reference Table
| Pound square feet (lb·ft²) | Tonne square metres (t·m²) |
|---|---|
| 1 lb·ft² | 4.214 × 10-5 t·m² |
| 2 lb·ft² | 8.428 × 10-5 t·m² |
| 5 lb·ft² | 0.000210701 t·m² |
| 10 lb·ft² | 0.000421401 t·m² |
| 25 lb·ft² | 0.0010535 t·m² |
| 50 lb·ft² | 0.00210701 t·m² |
| 100 lb·ft² | 0.00421401 t·m² |