Conversion Tables, Constants, and Material Properties

General conversion factors (to five significant digits)

Quantity U.S. unit SI equivalent

Length 1 in 0.025400 m

1 ft 0.30480 m

1 mile 1609.3 m

Area 1 in2 0.64516 × 10−3 m2

1 ft2 0.092903 m2

1 acre 4046.9 m2

Volume 1 in3 0.016387 × 10−3 m3

1 ft3 0.028317 m3

1 US gallon 3.7854 × 10−3 m3

Conversion factors for stress analysis

Quantity U.S. unit SI equivalent

Density 1 slug/ft3 = 1 lbf s2/ft4 515.38 kg/m3

1 lbf s2/in4 10.687 × 106 kg/m3

Energy 1 ft lbf 1.3558 J (N m)

Force 1 lbf 4.4482 N (kg m/s2)

Mass 1 slug = 1 lbf s2/ft 14.594 kg (N s2/m)

1 lbf s2/in 175.13 kg

Power 1 ft lbf/s 1.3558 W (N m/s)

Pressure, Stress 1 psi (lbf/in2) 6894.8 Pa (N/m2)

Conversion factors for heat transfer analysis

Quantity U.S. unit SI equivalent

Conductivity 1 Btu/ft hr °F 1.7307 W/m °C

1 Btu/in hr °F 20.769 W/m °C

Density 1 lbm/in3 27680. kg/m3

Energy 1 Btu 1055.1 J

Heat flux density 1 Btu/in2 hr 454.26 W/m2

Power 1 Btu/hr 0.29307 W

Specific heat 1 Btu/lbm °F 4186.8 J/kg °C

Conversion Tables, Constants, and Material Properties http://www.sharcnet.ca/Software/Abaqus/6.11.2/books/p...

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Conversion factors for heat transfer analysis

Quantity U.S. unit SI equivalent

Temperature 1 °F 5/9 °C

Temp °F 9/5 × Temp °C + 32°

9/5 × Temp °K − 459.67°

Important constants

Constant U.S. unit SI unit

Absolute zero −459.67 °F −273.15 °C

Acceleration of gravity 32.174 ft/s2 9.8066 m/s2

Atmospheric pressure 14.694 psi 0.10132 × 106 Pa

Stefan-Boltzmann constant 0.1714 × 10−8 Btu/hr ft2 °R4 5.669 × 10−8 W/m2 °K4

where °R = °F + 459.67 where °K = °C + 273.15

Approximate properties of mild steel at room temperature

Quantity U.S. unit SI unit

Conductivity 28.9 Btu/ft hr °F 50 W/m °C

2.4 Btu/in hr °F

Density 15.13 slug/ft3 (lbf s2/ft4) 7800 kg/m3

0.730 × 10−3 lbf s2/in4

0.282 lbm/in3

Elastic modulus 30 × 106 psi 207 × 109 Pa

Specific heat 0.11 Btu/lbm °F 460 J/kg °C

Yield stress 30 × 103 psi 207 × 106 Pa

Consistent units

Quantity SI SI (mm) US Unit (ft) US Unit (inch)

Length m mm ft in

Force N N lbf lbf

Mass kg tonne (103 kg) slug lbf s2/in

Time s s s s

Stress Pa (N/m2) MPa (N/mm2) lbf/ft2 psi (lbf/in2)

Energy J (N × m) mJ (10−3 J) ft lbf in lbf

Density kg/m3 tonne/mm3 slug/ft3 lbf s2/in4

Conversion Tables, Constants, and Material Properties http://www.sharcnet.ca/Software/Abaqus/6.11.2/books/p...

2 of 2 Sunday 29 September 2013 12:39 PM