Document rpGmn2VyNYvma08e6myR98Zjq

American Society of Heating and Ventilating Engineers Guide, 1930 420, F ig . 2; S te a m Se r v ic e a n d M eter C o n n ec tio n s w,TM a t e r P r e h e a te r^ Chapter 25--District Heating Table 1 shows the expansion in 100 ft. of pipe, at various temperatures. The expansion of any length of pipe is determined by. taking the difference Table 1. Expansion of Pipe in Inches per 100 Ft. Temperatube Deo. Fash. 0 10 20 30 40 50 100 150 200 250 300 350 400 Wrought. Iron os Steel 0.00 0.08 0.15 0.23 0.30 0.38 0.76 1.15 1.57 1.99 2.47 2.94 3.46 Cast Iron 0.00 0.05 0.10 0.15 0.25 0.36 0.72 1.10 1.50 1.90 2.35 2.80 3.30 Copper and Brass 0.00 0.13 0.25 0.35 0.45 0.57 1.14 1.75 2.38 3.02 3.74 4.45 5.24 Table 2. Length of Expansion Offsets and Bends for Proper Expansion of Pipe Total Expansion 1 2 3 4 5 6 7. 8 Feet op Pipb and Offset ob U-Bbnd fob different Diameters of Pope 2' 3* 4' s* 6' 8* 10* 12* 14' 16* u 13 15 17 19 21 23 25 27 30. 15 18 21 23 26 29 32 35 38 42 18 22 26 29 32 36 40 43 48 52 21 26 30 34 37 42 47 so 56 58 24 30 34 38 41 47 53 57 63 65 27 33 37 41 45 52 58 63 69 71 30 36 40 44 48 56 62 .68 74 .... 32 39 43 47 52 60 66 72 -- This column shows the total expansion the offset will take care of without a cold strain. . In general these amounts can be increased 40 per cent which increase can be taken up in cold strain of the pipe on being made up. The length of pipe in the expansion piece should be the same whether in the form of a single right-angle offset or double offset or U-Bend. The lengths of arms figured for 12.000 lb. per square inch tension for wrought iron pipe. If steel pipe is used this is good for 16,000 lb. per inch so that the arm will take care of more expansion. in expansion at minimum and maximum temperatures and dividing by 100 to arrive at the expansion per foot, then multiplying by the number of feet of pipe for which expansion is to be figured. In the installation of transmission lines it is frequently the practice to figure on an installation temperature of 70 deg. fahr. and to com pensate for about 40 per cent of the total expansion by means of a cold strain put in the line at the time of installation. This allows for only 60 per cent of all expansion to be taken care of by expansion joints, offsets or bends. Table 2 gives the length of pipe that should be made up to provide for the expansion'.' -In general the arms should be made up with pipe bends which can be welded into one continuous length. 421 '. /