Document dn90EXkvgOxJEdRbpb142B7QG

American Society of Heating and Ventilating Engineers Guide, 1930 Table 12. Properties of Gases* Gas CHEMI CAL Symbol Ntm- or AtomsI Molecular Weight Approx* Exact imate 0*=32 Weight in Pound or 1 Cu. Ft. at Atmos- . At 62 At 32 Den sity Gab Rbla* Con TIVE stant TO R Am Specific Heat PER Pound Cp Specific Heat per Cubic Foot at Atmospheric Pressure AND 62 Dxo. Fahb. ev Helium Argon. Air. Oxygen. j 0> Nt Hi NO CO 4.0 40.0 29.0 32.0 28.0 2.0 30.0 28.0 4.0 0.0105 39.9 0.1048 28.95 0.0761 32 0.0840 28.08 0.0737 2.016| 0.00529 30.04 0.0789 28.00 0.0734 0.0112 0.1112 0.0807 0.0892 0.0783 0.00562 0.0838 0.137 386.0 1.25 U78 38.70 0.124 1 53.34 0.241 1.105 48.25 0.217 0.970 54.99 0.247 0.0696 765.86 3.42 1.038 51.40 0.231 0.0780 0.968 55.14 0.243 0.75 0.0131 0.075 0.0131 0.171 0.0183 0.155 0.0182 0.176 0.0182 2.44 0.0181 0.165 0.0183 0.172 0.0180 0.0079 0.0079 0.0130 0.0130 0.0130 0.0129 0.0130 0.0126 HC1 COi NjO SO* NHj CjHt CHjCI CHa CtH 36.5 44.0 44.0 64.0 17.0 26.0 50.5 16.0 28.0 36.45 0.0958 0.1017 44.00 0.1156 0.1227 44.08 0.1157 0.1229 64.06 0.1684 0.1786 17.06 0.04483 0.0476 26.02 0.0684 0.0725 50.47 0.1326 16.03 0.0421 28.03 0.0738 0.1407 0.0447 0.0780 oFrom Marks ' ifechanicai Engineers' Handbook. 1.260 1.520 1.522 2.213 0.590 0.899 1.744 0.554 0.969 42.35 0.191 0.136 0.0183 0.0130 35.09 0.210 0.160 0.0243 0.0185 35.03 0.221 0.171 0.02S6 0.0198 24.10 90.50 59.34 0.154 0.523 0.350 0.123 0.399 0.270 0.0260 0.0234 X024 0.0207 0.0178 0.0185 30.59 0.24 0.20 ().032 96.31 55.08 0.593 D.4Q 0.450 1025 0.33 < .029 0.0265 0.019 0.024 1.41 1.40 1.31 1.26 1.25 1.31 1.28 1.20 1.32 1.20 522 CHAPTER 34 SYMBOLS AND ABBREVIATIONS Symbols for Heat, Thermodynamics and Hydraulics; Abbreviations; Drafting Room Practice. IN this chapter there will be found the symbols for drawings adopted by the A. S. H. V. E. in its Code of Minimum Requirements for the Heating and Ventilation of Buildings as well as A. 5. A.1 tentative standard symbols and abbreviations for scientific and engineering terms, also some recommended standards for drafting room practice. The following distinction between symbols and abbreviations is made: A symbol is a letter or sign used in a formula as a substitute for any numerical value. A shortened expression for a name or a unit is an abbreviation and not a symbol. SYMBOLS FOR HEATING AND VENTILATING DRAWINGS2 1. The objects of this standard set of symbols are to insure the correct interpretation of drawings and to conserve drafting room time by establishing simple and unmistakable symbols for the component parts of the heating and ventilating systems. In preparing the list of symbols an effort has been made to follow existing practice in so tar as possible but the list cannot be expected to match exactly the existing practice of every drafting room. 2. Simplicity, ease of execution and unmistakable identification were carefully' con sidered in selecting the symbols. Uncommon fittings and appliances such as vacuiftn pumps, separators, etc., have purposely been omitted in order to produce a list which can be easily remembered. It is assumed that when the scale of the drawing permits, the valves and fittings will be drawn to scale and a conventional representation is then unnecessary. 3. High pressure steam supply pipe .............. -- 4. Low pressure steam supply pipe ------------------- 5. Hot water pipe--flow ------- ------ 6. Return pipe--steam or water 7. Air vent line 'The compilation of these standards is undef the supervision of the American Standards Association. and the sponsor organizations include: American Associationfpr the Advancement of Science; American Institute of Electrical Engineers; American Society of Civil Engineers; Societyfor the Promotion of Engineering Education, and American^Society of Mechanical Engineers. 'From A. S. H. V.' E. Code op Minimum Requirements for the Heating and Ventilation op Buildings. 523