Document Dvwpx7Q7wjg91wweG6Da4y1Rn

r American Society of Heating and Ventilating Engineers .Guide, 1932 Table 14. Pipe Sizes for Two-Pipe Vapor Heating Systems, where Equivalent . Length of Run from Boiler or Source of Supply to Farthest Radiator Exceeds 200 Ft. Capacity in Sq. Ft.' of Equivalent Radiation Based on 4 oz. Total Pressure Drop PlFB Size Inches Equivalent Length or Pm from Boiler to Farthest Radiator, Including Main and Riser. (See Note 6.) Supply Main Dripped and Branches to Risers Dripped-- Steam and Condensate flowing in same direction. 100 Ft 200 Ft 300 Ft 400 Ft 500 Ft 600 Ft Maximum Capacities Supply Risers Up-Feed Branches`to Supply Risers and Radiators Not Dripped Return Risers X IX IX 2 2X 3 3X 10 12 ill 245 380 771 1270 2326 3474 4914 9092 14,924 31,066 56,689 90,985 79 173 269 546 898 1645 2457 3475 6429 10,553 21,967 40,085 64,336 65 141 220 446 734 1342 2006 2828 5250 8618 17,935 32,730 52,530 56 122 190 386 635 1163 1737 2457 4546 7462 15,533 28,345 45,492 49 110 165 345 568 1040 1552 2196 4062 6669 13,880 25,334 40,660 46 100 155 315 518 948 1419 2011 . 3712 6094 12,682 23.144 37.145 30 190 56 26 450 122 58 . 990 190 95 .1500 386 195 3000 635 395 1129 1548 700 1150 2042 1700 3150 Different makes of supply and return Tslrei, steam traps and other specialties vary as to capacity, therefore uae.ssxe as recommended for any particular make. Vertical connection* to be of same size as ralre and trap used. Return hori zontal runout to be not less than K in. Pipe Size Inches Drt Return Main Equivalent Length or Run from Boiler to Farthest Radiator in Feet Wet Return Main Equivalent Length of Run from Boiler TO Farthest Radiator in Feet 100 200 300 400 500 600 100 200 300 400 500 . 600 KL MN 0 P Q R S T V V W i 460 412 368 320 275 227 1400 1000 820 700 590 480 IX 962 868 770 670 579 480 2400 1700 1420 1200 1020 860 ix 1512 1362 1210 1058 909 757 3800 2700 . 2260 1900 1560 1300 2 3300 2960 2640 2300 1980 1630 8000 5600 4500 4000 3360 2800 2X 5450 4900 4380 3800 3300 2770 13,400 9400 7600 6700 5700 4800 3 10,000 9000 8000 7000 6000 5000 21,400 15,000 12,300 10,700 9300 7800 3X 14,300 12,900 11,500 10,000 8600 7200 32,000 22,000 24,000 16,000 13,600 11,400 4 21,500 19,300 17,200 15,000 12,900 10,700 44,000 31,000 26,000 22,000 20,500 15,400 .. ,/ American Sociktt or IlnATiNO AND Ventilatino Engi-veess 1 Not to be Reprinted WithtrOpyrtgnt, twr | Heating and Piping Contractor! National Auociaiion / out Special Permission 154 Chapter 9--Steam Heating Systems and. Pipe Sizes INSTRUCTIONS FOR USING TABLE 14 al. Radiator branches more than 8 ft. in length should be one size larger than shown in Column I. 2. This table is for systems which are open to atmosphere or operate under slight pressure or partial vacuum without use of vacuum pumps. 3. These tables apply where pipes are properly reamed. No allowances for defective material or workmanship have been made. (Also see Tables 7 and 8). 4. Capacities based on A lb. condensation per square foot per hour equivalent radia tion and actual diameter of standard pipe. 5. Extra length to be added to straight run of pipe for various fittings and valves to determine equivalent length. (See Table 4). 6. Mains are to be proportioned according to the equivalent length of run from the boiler or source of supply to the farthest radiators supplied by the main. Determine equivalent length of run then use figures in corresponding Columns (B to G) for supply mains; (L to Q) for dry-return mains; (R to W) for wet-return mains for sizing the entire run. For example: If the distance from boiler or source of supply to the farthest radiator on the longest main should be 300 ft., all mains are to be sized from Column D; if 400 ft., Column E; if 600 ft. Column C. Supply and return risers are to be-proportioned according to the equivalent length' of run from the boiler or source of supply to the farthest radiator on each riser. For supply risers determine the distance from the boiler to the farthest radiator served by that riser then use the figures in the corresponding Columns (B to G) for sizing each supply riser; providing the amount of radiation for that riser does not exceed amounts shown in Column H. Where supply riser capacities are found to be' in excess of amounts shown in Column H, step up to necessary size indicated in that column. For example: If the distance from the boiler or source of supply to the farthest radiator on a supply riser is 300 ft., that riser is to be sized from Column D, providing the amount of radiation does not exceed the amount shown in Column H. If the amount exceeds that in Column H, use amounts shown in Column H for sizing that entire riser. If another riser taken from the same main ais the one indicated is only 200 ft., this riser should be sized from Column C, providing the amount of radiation does not exceed that as shown in Column H. For return risers determine the equivalent length of run in feet from the top of each riser to the boiler then use the figures in the corresponding Columns (Z, to Q) for sizing each riser. For example: If the distance from the boiler or source of supply to the farthest radiator on'a return riser is 300' ft., that riser is to be sized from Column N, providing the amount of radiation does not exceed the amount shown in Column J. If the amount exceeds that in Column J, use amounts shown in Column J for sizing that entire return riser. 7. For practical purposes the pipe sizes on the usual heating system may be deter mined by using the pressure drop indicated by the longest main and riser on that system, neglecting the separate computations for each separate shorter run. 8. Where it is necessary to drip a supply main or a supply riser or a branch to a supply riser, same should drip separately into a wet return. The drip for a vapor or a vacuum system may be taken into a dry return through a steam trap.. 9. Pitch of mains should be not less than-Ji in. in 10 ft.; on horizontal branches to radiators and risers at least X in. in 10 ft. 10. In general it is desirable not to have a supply main smaller than 2 in. in diameter. When the supply main is larger than 2X in. at the beginning, it is desirable that it shall not be smaller than 2X m. at the end. 155