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892 CHAPTER 58 1965 Guide-And Data Bo6k " Tabfe-'20v. .". Application of Pipe/Tube, and-Rttings for Heating and Air Conditioning - CHHledw&ter Cooling tower Underground water 2-in. and smaller 2>4-in. and larger City water--inside building Materitt* Cemomnfy Uted Type K or' L hard copper, wrought iron, or black steel. Schedule 40 Type K or L hard copper, - wrought iron, or black steel. Schedule 40 Type K soft copper, galvan- , ized. wrought iron, or gal vanized' steel, Schedule 40 (for corrosive soils,'a coated steel pipe should be used) Type E, soft copper, cast iron. Class 150, -galvanized wrought iron, or galvanised steel. Schedule 40'(for cor rosive soils, a coated steel pipe should be used) Type E or L hard copper, gal vanized wrought iron, or galvanized steel. Schedule "40 ` i;. AppUcaHoa Hot water heating* Steam heating . Supply . . 125 psi and less 125 to 250 pa Return pipe / -AH sizes Receiver vent . .All sizes Type K or L hard copper, black' sted, or 'wrought iron! Schedule 40 ......... Type K or L hard,- copper, wrought iron or; black sted. .,, Schedule' 40 Type L hard .copper,. black steel,' Schedule 40, standard - fittings Type E hard copper, . steel. Schedule .40. Type E or L> hard copper,1 black wrought iron or steel. Schedule 40. Standard - fit-. , tings . Copper drainage tube DWV; , galvanized wrought .iron -or steel, Schedule 40. Standard fittings Underground rain water con ductors Rmttl inqtAllntiona Vitrified clay or`cast-iron, soil - Under paved areas - Vitrified clay or cast-iron soil" ' 8-UL. and omollor ' Cast-iron soil XH or vitrified' --day ^ 10 to .24-in.';'- .. Vitrified clay-or.concrete - - 30-in. and larger- ,-t q Vitrified clay or concrete 5, feet outside bldg., and Cast-iron soil XH or vitrified tinder paving . ' ` day "'' ( .Interior--rain water - conduc-' ;':..;.tore . .I;-!'--.::-.- 'Small installations Copper. drainage, tube DWV, black or'galvaiuzed wrought iron or steel Schedule'40 ' I^rge installations - Copper drainage -tube - DWV, cast-iron soil XH, black or galvanized wrought iron or steel. Schedule 40 Sanitary* Pmoil ingfallofin . Waste: . lX-in. and smaller 2-in. and larger Vents: i * : 2J4-in. and ntnollop , 3-in. and larger Largo installations Waste: 2-in. and larger Vents: - '' 24b. and larger Copper drainage tube DWV, galvanized wrought" iron or - steel,' Schedule 40 Cast iron, copper drainage tube DWV, galvanized sted, Schedule 40, or vitrified clay Copper drainage, tube DWV, - galvanized wrought iron . or steel. Schedule 40 ' ., Cast iron, copper drainage -.tube." DWV, or galvanized sted. Schedule 4Q^ Cast iron, galvanized steel, Schedule 40, copper drain age tube DWV or vitrified clay1' ; '` ' Cast iron, galvanized steel, .- Schedule 40, or copper drain- age tube DWV : Panel beating* Type K or L hard ofsoft cop per, black steel'or'wrought -`troo, Schedule 40 Gas (all kinds) All sizes Black sted, Schedule 40, mal leable iron fittings * Panel hretinf copper fittiaz* boold be uttered with BA-6 * AH naderpoond feed esd ipturo line# buried in abb, ebooId be * Befnccnnt fittiap on eopper-pipe most be wrought copper. AH * Bouae eower to nsain chouid be-ost iron XH. * Material* moat comply with local plumbing eodae. fittings fTMld be welded. , - with fitting* ee outlioed for panel beating, fitting* aboaU be mm ./ action of a column under excessive compression.. In fact, a pipe line in compression is- identical to a column. Column criteria can therefore be used for selecting the action of sup ports to resist lateral thrust;;.- A common equation for determining safe column loads is Euler's formula: 8-- ("7") ^or cas1, lron 868 Equation's) (6) trhere 8 allowable column load, pounds per square inch. k " radius of gyration, inches. I " column length, inches. , - f-i- (D.)* + (Di)* 16 Pipe, Tube, and fittings!..: 893 Equation 5 is sometimes modified by a correction factor' C to the fpllowing: S - C.>b(y)' (6) From Equation 6: ;/: /TcF . v .`-'`r ,,.,s. <7? ' This equation is not'used for colunm, construction''but is efficiently accurate for'the work of a heating engineer. . The equation is modified for cast iron because of its-poor tennile strength! It'is' gener^y 'acceptable' toiuse' one-half the value of S from Equation 5. for cast-iron, so.'.the- safe column load Si for cast' iron is: - ~ for'cast iron. f` (8) It is permissible to allow the l/k ratio for steel to go as high as 120, but for cast iron the desirable maximum is taken as 70.. It is not to be understood that a fracture will occur at l/k ratios in excess of those given, rather it is to be understood that lateral support should be given for those ratios and for those magnitudes of stress. If an expansion joint is used, this will, of course, relieve the compressive stress. Example t: For Example 1 given in the preceding section, the constraining force for a 1-in. pipe was 9630 lb. What is a required spacing for lateral support for this pipe? Answer: Using Euler's formula, Equation 5 gives: so l - xky/E/S For a 1 in. Schedule 40 steel pipe k - 0.4205 in. E - 30,000,000 psi. S = 9630 + 0.494 - 19500 psi. I - 51.8 in. Therefore, lateral supports on 4-ft centers are adequate. The other type of load requiring some support is the bend ing stress due to the weight of the pipe, its insulation.and of the fluid being carried. There is dm the bending moment that may be caused by the flexure of the pipe. A Hiscmaonn of flexure loading is beyond the scope of this chapter. Since hangers should always be designed to take the bend ing moment (including buckling) from the pipe, it is neces sary to design the hangers or supports for the maximum bending stress. Even with perfect support spacing there will be some sagging; therefore, the supports should be on a gradient if it is necessary to prevent pockets. Such a condi tion arises for condensate piping. Typical bending and deflection equations are given in Table 18, in order that supports can be properly sized, and, if neces sary, pitched. These equations are typical beam equations. If more complex loadings exist, proper beam equations can be applied. Such equations are found in standard texts on mechanics of materials. The recommended maximum gpaemg 0f hangers and the minimum diameter of hanger rods are given in Table 19. By application of the equations given in this section and - -Table 21......Relative Cost- Index for Schedule '40 Steel-Pipe and-Xype L HardtCapperiTube* - NoeWhtt Sbt, <a H - H i IX . IK - Schedaie 40 Steel Pipe . Type 1, Herd Copper , Jubm.l t........ '; 0.30 0.46 0.54 0.61 0.66 .' ` ."0.19? ' 0.25 _ 0.28 . 040 0.46. 2 '' ...... 2X 3: 4 ,. 5 _ ... ' 0.76' 1.00 1.25 1.632.19 v 6 ' 2.87` 8 3-44 10 4.52 12 5.67 * Ccet utter I* baaed oa material and labor e 0.68 " ' 1.00 ' ' 1.25 2.00 2.90 ... .f 365 -- -- -- the section on Expansion and Flexibility, it is possible to de termine the proper location and type of support for straight* lines. There are two types of supports, anchors and hangers. Anchors are used to guide the expansion or to fix the pipe. They are needed to take the stress out of the line and trans late the stresses to the foundations. In that way, all stress can be taken out of the line before it can be transferred to such equipment as boilers or pumps. By means of solid anchors, the anchors can be used to divide the piping into isolated sec tions that cannot transmit the stresses to other sections. Hangers are used to support the piping and to take out the bending stresses. They are of the spring, roller, or rod type. Such types generally allow the free movement of the pipe and yet maintain full support. The Code for Pressure Piping, ASA B31.1, has strict re quirements for the materials used in hangers and supports. The structural properties have a safety factor of five, and con sequently there is little chance of failure due to a sudden change of load. There is a type of support for almost every conceivable re quirement. Complete information can best be obtained from a hanger manufacturer. APPLICATION OF PIPE, TUBE, AND FITTINGS In the application of pipe, tube, and fittings it is necessary y to comply with regulations contained in local codes and ordi nances and in voluntary industry codes.1'1 Table 20 is offered as a guide to current practice in heating and air conditioning. It is based on practice in a number of consulting engineers' offices and information extracted from Reference 8- It should be borne in mind that selection of material to be used will also be influenced by the familiarity of local artisans with methods of using different materials. Economic Considerations Table 21 shows the comparative installed oosts of Type L copper and Schedule 40 steel pipe. The data in Table 21 were