Convert Poises to Pound-force seconds per square inch
Convert Poises (P) to Pound-force seconds per square inch (lbf·s/in²) instantly and accurately.
Conversion Formula
lbf·s/in² = P × 1.450377377e-5
About Poises
The poise (P) equals 0.1 Pa·s (exact), defined in the CGS system as 1 g/(cm·s). Named after Jean Louis Marie Poiseuille, it was the dominant viscosity unit before SI adoption. Fluid-mechanics textbooks and older ASTM and API data tables still list viscosities in P. Motor oil at 100 °C is ≈0.02-0.05 P; water at 20 °C is ≈0.01 P (= 1 cP). 1 P = 0.1 Pa·s = 100 cP.
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
| Poises (P) | Pound-force seconds per square inch (lbf·s/in²) |
|---|---|
| 1 P | 1.45 × 10-5 lbf·s/in² |
| 2 P | 2.901 × 10-5 lbf·s/in² |
| 5 P | 7.252 × 10-5 lbf·s/in² |
| 10 P | 0.000145038 lbf·s/in² |
| 25 P | 0.000362594 lbf·s/in² |
| 50 P | 0.000725189 lbf·s/in² |
| 100 P | 0.00145038 lbf·s/in² |