Document pm1VVjJRvL5GyMzO9NBvEz7Kd

American Society of Heating and Ventilating-Engineers Guide, 1936 Table 6. Length in Feet of Pipe to be Added to Actual Length of Run-- Owing to Fittings--to Obtain Equivalent Length____________ Sob of Pipe Inches St*d. Elbow Side Outlet Tee Gate Valve Globe Valve Angle Valve Length in Feet to be Added to Run 2 2H 3' ' 3H 4 5 6 7 8 9 10 12 14 r 5 7 10 12 14 18 22 26 31 35 39 47 53 16 20 26 31 35 44 50 55 63 69 76 90 105 2 18 9 3 25 12 3 33 16 4 39 . 19 5 45 22 7 57 28 9 70 32 10 82 37 12 94 42 13 105 47 15 118 52 18 140 63 20 160 72 Example of length in feet of pipe to be added to actual length of run. MEASURED LEHSTH. - BR.-O. 4'GATE YALtE. - 5-0. I 1 4-4'ELBOYfS. - S6-0 EOVtYALEHT LEHSTH - 193-0' H TABLES FOR PIPE SIZING1 Factors determining the size of a steam pipe and its allowable limit of capacity are as follows: 1. Pipe condensate flowing with steam. 2. Pipe condensate flowing against steam. 3. Pipe and radiator condensate flowing with steam. 4. Pipe and radiator condensate flowing against steam. It is apparent that (3) and (4) are practically limited to one-pipe systems while (1) and (2) cover all other systems. . Tables.7 and 8, worked out for determining pipe sizes, have their col umns lettered continuously, Columns A through Z, being in Table 7, and M through EE in Table 8. In the following text, reference made to columns will be by letter. The tables are based on the actual inside diameters of the pipe and the condensation of M lb (4 oz) of steam per square foot of equivalent direct radiation2 (abbreviated EDR) per hour. The drops indicated are drops in pressure per 100 ft of equivalent length of run. The pipe is assumed to be well reamed without unusual or notice able defects. *Aa steam system design has materially changed in recent years so that 240 Btu no longer expresses the heat of condensation from a square foot of radiator surface per hour, and as present day.heating units have different characteristics from older forms of radiation, it is the purpose of The Guide to gradually eliminate the empirical expression square foot of equivalent direct radiation, EDR, and to substitute a logical unit based on the Btu. The new terms to express the equivalent of 1000 Bfii-(Mb), and lOOO Btu per hour (Mbh), have been approved by the A.S.H.V.E. 562 Chapter 32--Piping for Steam Heating Systems Table 7. Steam Pipe Capacities Capacity Expressed in Square Feet of Equivalent Direct Radiation (Reference to this table will be by column letter A through L) This table is based on pipe size data developed through the research investiga tions of the American Society of Heating and Ventilating Engineers. CAPACITIES OF STEAM MAINS AND. RISERS Direction of Condensation Flow or Pipe Line Special Capacities for One-Pips 8tbteics Onlt Pipe With the Steam in One-Pipe and Two-Pipe Systems In. 1/33 lb i/4lb i/ie lb ' or or or HO. H* 1 Os Drop Drop Drop Klb or 2 Os Drop K lb or 40z Drop Hib Two-Pipe Only or 80s Drop Vertical Hori zontal Supply Risers UpFeed Radiator Valves and. Vertical Con nections Radiator and Riser Run outs AB C D E F G He fo Jb K Lc % 30 i 39 46 56 79 in 30 25 157 56 26 45 m 87 100 122 173 245 346 122 58 98 134 155 190 269 380 538 190 95 152 2 273 315 386 2M 449 518 635 546 771 1,091 386 195 288 898 1,270 1,797 635 395 464 3 822 948 1,163 1,645 2,326 3,289 1,129 700 799 1,228 1,419 1,737 2,457 3,474 4,913 1,548 1,150 1,144 4 1,738 2,011 2,457 3,475 4,914 6,950 2,042 1,700 1,520 5 3,214 3,712 4,546 6,429 9,092 12,858 3,150 6 5,276 6,094 7,462 10,553 14,924 21,105 8 10,983 12,682 15,533 21,967 31,066 43,934 10 20,043 23,144 28,345 40,085 56,689 80,171 12 32,1681 37,145 45,492 64,336 90,985 128,672 -- 16 60,506 69,671 84,849 121,012 169,698 242,024 -- -- 20 55 81 165 . 20 55 81 165 260 475 745 1,110 2,180 -- 1 AH Horizontal Mains and Down-Feed Risers | UpFeed Risers Mains and Un dripped Runouts UpFeed Risen Radiator Con nections Run outs Not Dripped Note.--All drops shown are in pounds per 100 ft of equivalent run--based on pipe properly reamed. Do not use Column H for drops of 1/24 or 1/32 lb; substitute Column C or Column B as required. bDo not use Column J for drop of 1/32 lb except on sizes 3 in. and over; below 3 in. substitute Column B. cOn radiator runouts over 8 ft long increase one pipe size over that shown in Table 7. Conyri&ht {' ^1 musica* #Socibtt or Hratino and Ventilatino Engineers \ Not to be Reprinted Wlthl Heating, Piping and Atr Conditioning Contractors National AttodaU i j out Special Permission Table 7 may be used for sizing piping for steam heating systems by determining the allowable or desired pressure drop per 100 equivalent feet of run and reading from the column for that particular pressure drop. This applies to all steam mains on both one-pipe, and two-pipe systems, vapor systems, and vacuum systems. Columns B to G, inclusive, are used where the steam and condensation flow in . the same direction, while Columns H and I are for cases where the steam and condensation flow in opposite directions, as in risers and runouts that are not dripped. Columns J, K, and L are for one-pipe systems and cover riser, radiator valve, and vertical connection sizes, and radiator and runout sizes, all of which are based on the critical velocities of the steam to permit the counter flow of condensation without noise. Sizing of return piping may be done with the aid of Table 8 where pipe capacities for wet, dry, and vacuum return lines are shown for the pressure drops per 100 ft corresponding to the drops in Table 7. It is customary to use the same pressure drop on both the steam and return sides of a system. 563