Note: Conversion Factors Are Given Here to Generally Three Or Four Significant Figures

Conversion Factors

Note: Conversion factors are given here to generally three or four significant figures.

Mass Standard SI unit: kilogram (kg). Equivalent unit: N.s2/m.

Force Standard SI unit: Newton (N). Equivalent unit: kg.m/s2.

Length

Area

Volume

Volume Flow Rate

Density (mass/unit volume)

Specific Weight (weight/unit volume)

General Approach to Application of Conversion Factors. Arrange the conversion factor from the table in such a manner that, when multiplied by the given quantity, the original units cancel out, leaving the desired units.

Example 1 Convert 150 gal/min to the units of the units of m3/s:

(150 gal/min) = 9.46 x 10-3m3/s

Pressure Standard S1 unit: Pascal (Pa). Equivalent units: N/m2 or kg/m.s2.

Note: Conversion factors based on the height of a column of liquid (e.g. inH2O and mmHg) are based on a standard gravitational field (g = 9.80665 m/s2), a density of water equal to 1000 kg/m3, and a density of mercury equal to 13595.1 kg/m3, sometimes called conventional values for a temperature at or near 0oC. Actual measurements with such fluids may vary because of differences in local gravity and temperature.

Stress Standard S1 unit: Pascal (Pa). Equivalent units: N/m2 or kg/m.s2.

lb/in2 = psi lb/ft2 = psf 1000psi = ksi

Energy Standard S1 unit: joule (J), Equivalent units: N.m or kg.m2/s2

Power Standard S1 unit: watt (W), Equivalent unit: J/s or N.m/s

Dynamic Viscosity (m, or h) Standard S1 unit: Pa.s or N.s/m2 and cP = centipoise

Kinematic Viscosity (n) Standard S1 unit: m2/s and cSt = centistoke

n(cSt) =

For conversions involving Saybolt Universal seconds use the following equations. For the temperatures beside 100 oF.

Coefficient A must be used based on the following formula: A = 6.061 × 10-5T (oF) +0.994 SUS @ T (oF) = SUS @ (100oF) × A

n(cSt) = 0.226t - t ≤ 100 SUS n < 20 cSt SUS = 3.7712n + 21.4678

n(cSt) = 0.220t - t > 100 SUS 20 cSt ≤ n ≤ 75 cSt SUS = 4.5216n + 4.6187

n > 75 cSt SUS = 4.632n

Temperature Conversions

Given the Fahrenheit temperature TF in oF, the Celsius temperature TC in oC is

TC = (TF – 32)/1.8

Given the temperature TK in oK, the absolute temperature TR in oR is

TR = 1.8TK TK = TC + 273.15 TR = TF + 459.67