Document NNGeQ6MB0D1GJ8x77jN4LBexy

606 CHAPTER 27 1952 Guide I' Table 5. Abba of Flanged Fittings, Squab Feet* Nominal Pipe Size (Inches) 1 1H 2 2H 3 3H 4 4H 5 6 `8 10 12 Flanged Coupling Standard Extra Heavy 0.320 0.383 0.477 0.672 0.841 0.945. 1.122 1.344 1.474 1.622 1.82 2141 3.43 4.41 0.438 0.510 0.727 0.84S 1.107 1.484 1.644 1.914 2.04 2.18 2.78 3.77 5.20 6.71 90 Deg Ell Standard Extra Heavy 0.795 0.957 1.174 1.65 2.09 2.38 2.98 3.53 3.95 4.44 5.13 6.98 10.18 13.08 1.016 1.098 1.332 2.01 2.57 3.49 3.96 4.64 . 5.02 5.47 6.99 9.76 13.58 17.73 Long Radius Ell Standard Extra Heavy * 0.892 1.0S4 1.337 1.84. 2.32 2.68 3.28 3.96 4.43 5.00 5.99 8.56 12.35 16.35 1.083 1.340 I.874 2.16 2.76 3.74 4.28 4.99 5.46 6.02 7.76 II.09 15.60 18.76 _ Tee Standard Extra' Heavy 1.235 1.481 1.815 2.54 3.21 3.66 4.48 5.41 6.07 6.81 7.84 10.55 15.41 19.67 1.575 1.925 2.68 3.09 4.05 5.33 6.04 7.07 7.72 8.52 10.64 14.74 20.41 26.65 CROss Standard Extra Heavy 1.622 1.943 2.38 3.32 4.19 4.77 5.83 7.03 7.87 8.82 10.08 13.44 19.58 24.87 2.07 2.53 3.54 4.06 5.17 6.95 7.89 9.24 10.07 10.97 13.75 18.97 26.26 34:11 * Including arena of accompanying flangea bolted to the fitting. Standard' thicknesses of 85 percent magnesia pipe covering are not exactly 1 in. However, the loss through any given thickness of insulation can be obtained by interpolation. Also, the losses through, any of the insulations given in Table 6 can be obtained by multiplying the losses obtained from Figs. 1, 2, or 3 by the factors given in Table 7. Pipes operating at high temperatures are frequently insulated to the Table 6. Thermal Conductivity (fc) of Vabious Type Pipe Insulations fob Medium and High Tempebatubb Pipe* Expressed in Btu per (hour) (square foot) (Fahrenheit degree temperature difference per inch) Types op Insulating Materials Drnhxtt Lb/Cu Ft Temp. Rangb op Accepted Use Mean Temperature, F Deg 100 '200 300 400 500 Corrugated Asbestos--Type Laminated Asbestos---Type1 - 11-14 11-13 15-17 18-20 30-35 10-15 25-30 13-15 Up to 600 F Up to 300 F Up to 300 F Up to 300 F Ud to 700 F Ud to 800 F Ud to 1900 F Up to 1200 F 0.39 0.45 0.51 0.57 0.63 0.80 0.51 0.59 0.49 0.57 0.65 0.39 0.40 0.63 0.34 0.44 0.45 o.ea 0.39 0.49 0.54 0.50 0.55 .0.72 0.44 0.49 ii `u i 0.54 - * Average values from laboratories for insulating materials of various manufacturers. Table 7. Pipe Covebinq Factobs Types of Insulating Materials Temperature Difference, Pipe to Am, F Deg 100 200 300 400 500 Corrugated Asbestos--Type Mineral Wool--Type............................-........................ Diatomaceous 8uica--Type................................................. Brown Aebeatoe Fiber--Type............................ ............. l.io 1.19 1.15 0.96 0.98 1.37 0.86 1.36 1.23 1.19 0.98 1.00 1.36 0.88 1.42 1.27 1.23 1.00 1.02 1.35 0.91 L02 1.05 1.35 0.93 i.oi 1.07 1.34 0.96 Pipelnsulation 607 best> advantage by combining a high temperature insulation near the pipe with a moderate or low temperature insulation around it as an outerflayer: By this method an efficient material may be used for each of the two tem perature ranges encountered. In calculating the heat loss through such a Fig. -1. Heat Loss Thbough 1 In. Thick 85 pebcent Magnesia Type Covering combination the mean temperature of each layer must. be determined along with the thickness of each. This is readily done in three or four calculations performed as a series of approximations, in which assumptions of thickness and mean temperature are adjusted as indicated in the dis cussion which follows. - In the case of a single thickness of pipe covering, the quantity of: heat