Document ezX1L53V0KkrX8jOokLDQYnq

American Society of Heating and Ventilating Engineers Guide, 1924-25 TABLE 45. MAXIMUM CAPACITY OF ONE PIPE LINES AT VARIOUS PITCHES Pitch of Pipe in Inches per 10 Ft: Nominal Diam. In. x 1 m 2IK x 1 IK 2m X i m 2m 1X IK IK 2 X' COND. B.t.u. Sq. Ft. Rad. Lb. per Hr. Loss per Hr. 240 B.t.u. Lb. per Hr. K' Sq. Ft. Rad. Loss per Hr. 240 B.t.u. 6.19 11.32 25.95 35.25 58.40 9.22 15.58 32.93 44.80 74.10 10.50 18.60 38.10 51.80 85.70 11.74 21.75 42.68 58.10 96.80 6,010 10,990 25,180 34,210 56,670 1" 8,950 15,110 31,950 43,470 71,910 2" 10,190 18,050 36,970 50,270 83,160 4" 11,390 21,110 41,420 56,350 93,240 25.0 45.8 104.9 142.6 236.0 37.3 63.0 133.0 181.0 299.5 42.5 75.2 154.0 209.3 346.5 47.5 87.9 172.6 234.8 388.4 7.48 13.02 29.00 39.30 65.20 10.00 17.30 35.75 48.60 80.50 11.40 20.55 40.80 55.50 91.90 12.19 22.31 44.07 60.00 99.21 7,260 12,630 28,140 38,140 63,270 IK' 9,700 16,790 34,690 47,160 78,120 3" 11,060 19,940 39,500 53,860 89,180 . 5' 11,830 21,650 42,760 58,220 96,270 30.3 52.6 117.2 159.0 263.5 40.4 70i0 144.5 196.5 325.5 , 46.1 83.0 165.0 224.0 371.5 49.3 90.2 178.2 242.6 401.1 The accompanying tables are all for low pressure steam, that is, with the radiator at atmospheric pressure. Table 46 gives the maximum capacity of various sized pipes for steam pressures up to 1 lb., and also the velocity for the same pipe with the radiator at atmospheric pressure. TABLE 46. RESULTS OF TESTS USING HIGH PRESSURE STEAM Nominal Size of Pipe In. Pitch op Pipe in Decrees Header Pressure Lb. per Sq. In. i 90 1 90 IK 90 IK 90 IK -0.05 IK 0.0833 l 18.0833 6.25 0.50 0.50 1.00 1.00 1.00 1.00 Radiator Pressure Lb. per Sq. In. Maximum Maximum Condensate Velocity Lb. Ft. per Hr. per Sec. 0.250.500.501.001.001.001.00- 24.49 26.35 49.90 72.58 27.27 21.30 31.63 30.1 31.8 34.2 36.4 13.7 14.2 37.2 Maximum Velocity with Radiator Open to Atmosphere Per Cent - Change from Maximum 30.1 30.1 35.2 38.S 14.6 15.8 36.5 00.0 +5.8 -2.8 -5.4 -6.2 -10.1 +1.9 54 American Society of Heating and Ventilating Engineers Guide, 1924-25 Table 47 gives the capacity of various sized lines with and without an angle valve. It will be noted that the valves used in these tests had a seat opening smaller than the internal area of the pipe. The capacity of such lines containing a valve varies from 63 to 95 per cent of the same line without the valve. NOMINAL Size of Pipe In. X i IK IK TABLE 47. RESULTS OF TESTS ON ANGLE VALVES Area of Pipe Sq. in. 0.537 0.835 1.459 1.927 Area Valve Seat Opening Sq. In. 0.4418 0.822 1.258 1.773 Per Cent of Area of Pipe 82.2 98.4 86.2 92.2 Maximum Pipe and Valve 9.68 22.10 30.00 46.13 Capacity Pipe Alone Per Cent of Capacity of Pipe Alone 13.52 23.30 47.5 68.5 71.6 95.0 63.1 67.4 The capacity of various sized lines with a globe valve is given in Table 48, with the valve stem both in a vertical and horizontal position. It will be noted that with the stem in the vertical position the capacity of such a line varies from 11 to 35 per cent of the capacity of the same line without such a valve. With the valve stem in the horizontal position the capacity of the line varies from 54 to 76 per cent of the capacity of the same line without the valve. In other words, the capacity of a globe valve is somewhat less than the capacity of a pipe of the same nominal TABLE 48. RESULTS OF TESTS ON GLOBE VALVES Pitch = 0.4 In. per Ft. Nominal Size In. iX IK IK Valve Stem--Vertical Capacity of Pipe and Valve Lb. per Hr. 1.38 7.73 13.20 18.81 Per Cent of Capacity of Pipe Alone 11.8 35.7 31.2 33.0 Valve Stem--Horizontal Capacity of Pipe and Valve Lb. per Hr. 8.83 14.06 22.88 32.00 Per Cent of Capacity of Pipe Alone 76.3 66.1 54.3 56.7 Nominal Size of Pipe and Valve In. X 1 IK lK TABLE 49. RESULTS OF TESTS ON GATE VALVES Area of Pipe Sq. In. 0.5373 0.860 1.459 1.927 Area of Valve Sq. In. 0.4418 0.809 1.208 1.743 Pitch 0.4 In. per Ft. Pitch = 90 dbg. fahr. Capacity of Pipe and Valve Lb. per Hr. 10.15 22.50 33.13 50.93 Per Cent of Capacity of Same Pipe Without Valve 85.9 94.0 100. 90.4 Capacity of Pipe and Valve Lb. per Hr. 10.55 18.78 32.50 52.00 Per Cent of Capacity of Same Pipe Without Valve 78.0 78.0 68.6 75.9 55