Document pBgddEbXGKayb4ko53ZNObjVj

Heating Venturing Air Conditioning Guide 1939 Fig. 1. Chart for Estimating Dollar Value of Heat Loss from Barb Iron Pipes. (See Table l)a This chart Is based on 100 linear feet per 1000 hours. For fractions or multiples' of these factors, multiply by proper percentage. monetary value of the loss of heat given in Table 1 may be obtained by means of Fig. 1 for various heating system efficiencies, temperature differ ences, and calorific values and costs of coal. To solve a problem, select the proper heat loss coefficient from Table 1 and locate this.value on the upper left hand margin of the chart. Then draw lines in the order indi cated by the dotted lines, the dollar value of the heat loss per 100 linear feet of pipe per 1000 hours being given on the upper right hand scale. In using this chart, the cost of coal should also include the labor for hand ling it, boiler room expense, etc. 736 ' Chapter 39. Piping and Duct Insulation Table 2. Heat Loss from Horizontal Bare Bright Copper Pipe Expressed in Btu per hour per linear foot per degree Fahrenheit between the pipe and surrounding still air at 70 F Nominal Pipe Size (Inches) a M 1 m i lA 2 2H 3 3'A 4 m s 6; 8, Hot Water (Type K Copper Tube) 120 F I50F 180 F 210 F Steam (Standard Pipe Sue Pipe) 227.1 F (5 Lb) 297.7 F 1 337.9 F (50 Lb) 1 (100 Lb) Temperature Difference S0F 0.180 0.236 0.290 0.340 . 0.390 0.490 0.580 0.680 0.760 0.940 1.020 1.160 1.460 80 F 0.210 0.275 0.338 0.400 0.463 0.525 0.675 0.788 0.888 1.000 1.200 1.375 1.725 110 F 0.218 0.291 0.354 0.418 0.473 0.600 0.709 0.848 0.946 1.045 1.255 1.410 1.820 140 F 0.229 0.307 0.373 0.443 0.507 0.628 0.750 0.871 1.000 1.107 1.320 1.500 1.890 | 157.1 F 0.299 0.357 0.440 0.510 0.598 0.719 0.840 0.987 1.114 1.210 1.335 1.465 1.685 2.100 227.7 F 0.338. 0.408 0.492 0.571 0.671 0.813 0.953 1.107 1.235 1.361 1.495 1.670 1.890 2.373 267.9 F 0.355 0:418 0.523 0.598 0.710 0.851 1.008 1.165 1.307 1.456 1.488 1.755 1.942 2.510 Table 3. Heat Loss from Bright Copper Pipe Given One Thin Coat of Clear Lacquer Expressed in Btu per hour per linear fool per degree Fahrenheit between the pipe ana surrounding still air at 70 F Nominal Pipe Size - (Inches) Hot Water (Type H Copper Tube) . Steam (Standard Pipe Sue Pipe) 120 F 150 F 180 F 210 F | 227.1 F 1 (5 Lb) 297.7 F (50 Lb) 337.9 F (100 Lb) Temperature Difference 50 F 80 F HOF 140 F 157.1 F- 227.7 F 267;9 F A 0.240 0.265 0.282 0.307- - 0.401 -6.461 0.478 - % 0.320 - 0.356 0.373 0.414 0.477 6.571 0.578 l 0.390 0.437 0.463 0.507 0.598 ' 6.681 0.710 m 0.470 0.537 0.554 0.614 0.700 6.812 0.840 m 0.540 0.612 0.645 0.714 1.208 0.966 0.990" 2 0.690 0.762 0.818 0.892 1.005 1.164 1.201 2 'A 0.840 6.937 0.991 1.085 1.178 1.361 1.420 3 0.960 1.025 1.135 1.270 1.400 1.625 1.700 3A 1.100 1.250 1.318 1.442 1.580 1.845 1.905 4 1.241 1.400 1.480 1.556 1.750 2.040 2.130 m 1.910 -2.240 2.350 - 5 1.480 1.685 1.790 1.965 2.130 2.415 2.610 6 1.700 1.936 2.052 2.272 2.450 2.810 2.990 8 2.200 2.500 2:630 2.854 3.120 3.425 3.730 Heat losses from horizontal copper tubes and pipes with bright, bright lacquered and tarnished surfaces are given in Tables 2, 3 and 41. In order to determine heat losses per linear foot of pipe from known losses per square foot, it is necessary to know the area in square feet per *Heat Los from Copper Piping, by R. H. Heilman {Heating Piping and Air Conditioning, September, 1933. p. 458). r - 737 -1