Document nmpgZV4qyjBb5qZGd90denbX2

526 CHAPTER 22 1954 Guide 2.Table Heat-Carrying Capacitt of Standard Black Pipes 20with Temperature Drop of Deg" Nominal Pipe Sizes % in. to 12 in., and Friction 4 to 800 rniUnches per fool (A = Capacity, Mbh. B = Velocity, inches per second) (iOne mihnch equals 0.001 in.) Nominal Pipe Sue,, Inches Milinch Fric tion Loss PER HFoot of Pipe >6 ** 1 1M 1*4 2 2H 3 3*i 4 5 i 4 6 8 10 12 14 16 20 25 30 35 40 50 . 60 70 80 100 150 200 300 400 500 600 800 A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B 0.75 1.35 2.85 1.5 1.7 2.1 5-4 11.3 17.0 33.0 53-1 2.4 2.9 3.2 3.8 4.3 95 5.0 141 5.5 197 6.0 363 7.0 i 0.9 1.8 1.7 2.1 3.6 6.75 14.0 21.2 41.3 66.4 2.6 3.0 3.6 4.0 4.7 5.3 119 6.2 176 6.9 248 7.5 456 8.8 1250 2320' 3730 9.6 11 12 2920| 4690 14, 16 1.05 2.1 2.0 2.5 4.2 3.0 7.9 16.4 24.8 48.4 77.9 3.5 4.2 -4.7 5.6 6.3 140 7.3 207 8.0 291 8.8 535 10 1850, 3440 5520 12 14 17 19 1.2 2.4 2.2 2.8 4.7 3-4 8.9 18.6 28.0 54.7 88.1 4.0 4.8 5.3 6.3 7.1 158 6.2 234 9.1 329 9.9 605 12 2100 3910 6270 la; 19 27 1.35 2.45 2.7 3.1 5.2 3.7 9.8 20.5 31.0 60.4 97.4 4.4 5.3 5.9 6.9 7.8 175 9.1 259 10 364 11 671 1 13 2320| 4330] 6950 IS 21 24 1.45 2.65 5.65 10.7 22.3 33.7 65.8 2.9 3.4 4.1 4.8 5.7 6.4 7.6 106 ' 190 8.5 9.9 282 11 397 12 731 1 14 4730 7590 23 26 1.55 2.85 6.05 11.5 24.0 36-3 70.8 3.1 3.6 4.4 5.1 6.2 6.9 8.1 114 9.7 205 11 303 12 428 13 787 11300! 2730 5100 8190 15 171 21 25 28 1.75 3.25 6.85 13.0 27.1 41.0 80.0 3.5 4.1 4.9 5.8 7.0 7.7 9.2 129 10 232 12 344 13 484 15 892 11470 3100 5790 1300 17 20; 24 28| 'Si 2.0 3.65 7.75 14.7 30.6 46.3 90.5 4.0 4.6 5.6 6.5 7.9 8.8 10 146 12 263 14 389 15 548 1010 17 19 6570 10560 32 36 2.2 4.4 4.0 8.55 16.2 33.8 51.2 5.1 6.1 7.2 8.7 9.7 100 11 162 13 290 15 430 17 607 1120 18 22 3900 30, |ll710 40 2.35 4.4 4.7 5.5 9.3 17.6 36.8 55.7 6.7 7.9 9.5 11 109 13 176 316 14 16 469 18 661 1220 20 23 4250, 7940,112780 27 33 39 44 2.55 4.7 10.0 18.9 39.6 59.9 5.1 5.9 7.2 8.4 10 11 117 13 189 15 341 505 18 20 712 1320 22 25 2.85 5.7 5.3 11.3 21.4 44.7 67.7 6.7 8.1 9.5 12 13 133 15 214 17 386 20 572 22 807 1490 24 29 4580 8570 113780 35 42 47 5190] 9720|115650 40 47 54 3.15 5.85 12.4 23.6 49.4 74.9 6.3 7.4 8.9 11 13 14 147 17 238 19 427 22 633 26 893 1650 2730 5760 110780 27 32 36 44 52 3.45 6.35 13.5 25.7 33.8 81.4 6.9 8.0 9.7 11 14 ,5 160 18 258 21 465 24 690 27 973 1800 2970 6280,|ll760 [ 18950 29 35 40 48 57 65 3.7 6-8 14.5 27.6 57.9 87.6 7.4 8.6 10 12 15 17 4.IS 8.3 5.2 1C 7.7 16.4 31.1 65.4 99.0 9.7 12 14 r IS 9.( 20.4 38. i 81. i 12 \l n 2 12 2C 6.0a 11.' 23.1 45. 95- V1 1 2( 2 14 2 7. > 13. ) 29. 56. ) 11 1 18 1 > 1 i 2 2 3 3* 8.7 j 16. l 34. ' 66. l 14 } 21 2 1 B 2 1 2 6 3)3 3 6 4 9 9.85 18. 3 39. 2 74. 8 158 23 9 2D 23 29 33 41 45 10. 9 20. 2 43. 2 82. 5 17 4 26 4 22 26 32 3 7 4 5 50 12. 7 23. 6 50. 5 96. 5 204 31 0 25 30 3 7 4 3 52 5 9 172 20 194 22 24C 2f 28 31 35 5 4 41 ' 48 47 1 54 52 1 60 61 0 70 278 500 22 26 743 29 1050 32 1940 37 3200 6770| 12690120440 43, 52 62 70 314 566 840 1190 2200 3630 2S 30 33 36 42 48 (44001[23200 70 39C 70< 105( 149C 2760 4560 32 3* 4 4a 53 61 18120 29220 101 46 3 83' 4 124C 175( 4i 5 3240 62 5360 71 11350, 21320,134400 87 104 118 57 1 43 104 ) 51 155 ) 6)) 219 3 65 4060 78 6730 90 114270 110 [26830 131 [43300 149 67 3 54 122)3 64 182 3 71 257 3 78 4780 92 7910, 105 16790 131580 |51000 129 154 175 705 1380 2060 291 0 5410 6 2 7 2 89 8 8 104 i 19040 35840 [57880 14! 174| 199 84 6 68 153 0 80 2280 89 322 0 97 5990 115 9930 132 |21100 162 [39740 193 64210 221 99 2 80 1790 94 2670 10 4 3780 11 4 7030 111670||24820| 135 155 191 46780 228 75620 260 ' For other temperature drops the pipe, cecities may be W,th a temperature drop of 30 deg. the capacities shown in this table are to be multiplied bj 1.5. Hot Water Heating Systems 527 alent number of elbows of the same pipe size which would have the same friction loss. An elbow is assumed to have the same friction loss as a straight pipe having a length equal to 25 diameters (nominal) of the elbow. The resistance of various types of fittings expressed in equivalent elbow resistance is shown in Table 1. The friction loss in pipes and tubing may be determined from Fig. 2 and Table 2 for black iron pipes, and from Fig. 3 and Table 3 for type L copper tubing. The scale at bottom of Figs. 2 and 3 is the heat carrying capacity in thousands of Btu per hour based on a 20 deg temperature difference between flow and return risers. In order to use the scale for other than 20 deg difference, refer to footnote under Figs. 2 and 3. . If the flow in a given pipe is calculated in pounds per hour, it may be FLOW OF WATER IN GALLONS PER MINUTE T Cw,f l. scale of chart is based on 20 deg temperature difference between flow and return risers, to hnd friction when temperature drop is other than 20 deg , multiply the actual heat conveyed by /_ 20\ .. Vactual temp. drop. and read the corresponding friction. converted to corresponding gallons per minute by dividing the flow in pounds by 500, after which the friction may be found by entering Figs, v 2 and 3 at the top scale reading which corresponds to the flow in gallons per minute as determined. Orifices drilled in plates inserted in pipe unions are convenient means for introducing friction, where required to balance various circuits. The friction losses caused by various sizes of orifices are given in Table 4. CLASSIFICATION OF SYSTEMS Gravity or forced systems of piping may be classified according to piping arrangement and type of circulation as shown in Table 5. Flow and return main piping (gravity systems) for one-pipe, two-pipe direct return, and two-pipe reversed return systems are shown in Figs. 4, 5, and 6, re-