Convert Pound-force seconds per square foot to Pound-force seconds per square inch
Convert Pound-force seconds per square foot (lbf·s/ft²) to Pound-force seconds per square inch (lbf·s/in²) instantly and accurately.
Conversion Formula
lbf·s/in² = lbf·s/ft² × 0.006944444444
About Pound-force seconds per square foot
The pound-force second per square foot (lbf·s/ft²) equals (9.80665 × 0.45359237) / 0.3048² ≈ 47.880 Pa·s, numerically identical to slug/(ft·s). It appears in US civil and structural engineering fluid mechanics, pump hydraulics texts, and older API pipeline standards. A key identity: 1 lbf·s/ft² = 1 slug/(ft·s) ≈ 47.880 Pa·s = 478.8 P.
About Pound-force seconds per square inch
The pound-force second per square inch (lbf·s/in², reyn) equals 144 × 47.880 ≈ 6 894.8 Pa·s. Informally called the "reyn" (after Osborne Reynolds), it is used in US tribology and bearing-design engineering, where oil-film viscosity in heavily loaded contacts is stated in reyn. Turbine bearing oils at operating temperature range 0.5-3 × 10⁻⁶ reyn. 1 reyn ≈ 6 894.8 Pa·s.
Quick Reference Table
| Pound-force seconds per square foot (lbf·s/ft²) | Pound-force seconds per square inch (lbf·s/in²) |
|---|---|
| 1 lbf·s/ft² | 0.00694444 lbf·s/in² |
| 2 lbf·s/ft² | 0.0138889 lbf·s/in² |
| 5 lbf·s/ft² | 0.0347222 lbf·s/in² |
| 10 lbf·s/ft² | 0.0694444 lbf·s/in² |
| 25 lbf·s/ft² | 0.173611 lbf·s/in² |
| 50 lbf·s/ft² | 0.347222 lbf·s/in² |
| 100 lbf·s/ft² | 0.694444 lbf·s/in² |