British units

NOTE U.S. customary units or British units, on left and SI units on right. 

Converted and interpolated from Thermodynamic Properties of KLEA 60, British units, < 1993 (20 pp.). Reproduced by permission. KLEA 60 is R32/125/134a (20/40/40 wt %). 

Converted and interpolated from British units shown in Theimodynamic propeities of KLEA 32, ICI Chemicals and Polymers, 1993. Reproduced by permission. 

TABLE 13.6 Filtration Parameters in Metric and British Units... 

PROPERTY SYMBOL BRITISH UNITS METRIC UNITS DEFINITIONS ... 

Science cannot be performed without an accurate system of measurement, which is globally standardized and compulsory. Units and standards of measurement are agreed upon and harmonized on an international basis by the Bureau International des Poids et Mesures in Sevres, France, and by the International Organization for Standardization in Geneva, Switzerland. The units and standards are then laid down in national laws. Nearly all countries have accepted the Systeme International d Unites (SI units) as their system of measurement. This also applies to countries that had been accustomed to use British units like Australia, Canada, South Africa and the United States. In Britain, SI units are official from January 2010. The valid standards are available from the competent bureaus, for example Bureau International des Poids et Mesures, www.bip.fr National Measurement Institute (Australia), www.measurement.gov.au National Institute of Standards and Technology (NIST, USA), www.physics.nist.gov/ Pubs/SP811/... 

Unless otherwise specified, British units are shown to indicate the dimension used in the book. 

I 11 ic arums groups of physical parameters arc calm-) Liter tin British units) ... 

As previously discussed, the SI unit of mass is the kilogram while the British unit of mass is the slug. The SI unit of force is the newton (N), given by Newton s second law. One newton of force results from accelerating a mass of 1 kg by 1 m/s2. 

The British unit of force is the pound (lb), once again given by Newton s second law ... 

Solution This is an open-ended problem, which has many possible solutions. We need to find the diameter of the barrel, the channel depth, and the screw speed needed to generate the head pressure. We shall assume a square pitched screw, and use British units (in, s, Btu, lbf). 

The pressure of the air, as already mentioned, varies with altitude indeed, at one and the same place it does not remain constant in consequence of variation m composition, the influence of wind, etc. A standard pressure, known as an atmosphere, has been chosen. The British unit is a column of mercury 29-905 inches in height, measured at 82° F. m London, and is equivalent to a pressure of 14-78 lb. per square inch. 

Table 6 presents a detailed list of conversion factors that can be used to convert between U.S.-British units and SI units, while Table 7 gives a simplified and abbreviated list of equivalences for converting unacceptable units commonly used by chemical engineers into acceptable SI units. 

Key Words Conversion factors, British units, metric units, physical constants, water properties, periodic table of the elements, environmental engineers, Lenox Institute of Water Technology. 

For British units, one should note that 32.174 lbm.ft/lbf-s = I=gc where Ibm is the pound mass unit and Ibf is the pound force unit. Force and mass are related by Newton s second law,... 

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