Convert Pound-force seconds per square foot to Pounds per inch-second
Convert Pound-force seconds per square foot (lbf·s/ft²) to Pounds per inch-second (lb/(in·s)) instantly and accurately.
Conversion Formula
lb/(in·s) = lbf·s/ft² × 2.681170713
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 Pounds per inch-second
The pound per inch-second (lb/(in·s)) equals 0.45359237/0.0254 ≈ 17.858 Pa·s, used in plastics extrusion and rubber compounding industries where inch-based dimensions are combined with mass-based flow analysis. Polymer melt viscosities at processing temperatures are sometimes quoted in lb/(in·s) in older US extrusion equipment manuals. 1 lb/(in·s) ≈ 17.858 Pa·s = 12 lb/(ft·s).
Quick Reference Table
| Pound-force seconds per square foot (lbf·s/ft²) | Pounds per inch-second (lb/(in·s)) |
|---|---|
| 1 lbf·s/ft² | 2.68117 lb/(in·s) |
| 2 lbf·s/ft² | 5.36234 lb/(in·s) |
| 5 lbf·s/ft² | 13.4059 lb/(in·s) |
| 10 lbf·s/ft² | 26.8117 lb/(in·s) |
| 25 lbf·s/ft² | 67.0293 lb/(in·s) |
| 50 lbf·s/ft² | 134.059 lb/(in·s) |
| 100 lbf·s/ft² | 268.117 lb/(in·s) |