Document 158mEMB1GwExrg2EzqJ6K1jX

m American Society of Heating and Ventilating Engineers Guide 8. For longer lines, manholes must He located according to judgment and a K upon the expansion value of the type of expansion joint or bend that is e*)eilliS minimum number of manholes will be required when an expansion bend orUS6t*' ' with double expansion joint is placed in each manhole and the pipes are3*1 ani midway between manholes. a,ich< 9. Stabilizers to maintain alignment of pipes should be placed on each sid expansion joint or bend. ae of ei 10. A proper hydrostatic test should be applied to the piping before the to conduit is applied and before application of insulation. The pressure used in S.should be greater than the pressure used in service, and should be not less than inn* per square inch in any case. 11. In most types of conduit construction a drainage system is provided ui tins sewers, c__u__u___s__u__u__ui..*u__i_i_i. or when tidal Tu_Tu__w___c__v__c_--i, wucic water is likely to acIu.e. s_ii__M___u__i 1m!_ica m,,e lm_ mJ give trouble, a separate d<irlainoar gneeasrys^thteemlleesJvvhepo`fjtvjf^!f be installed and connected to a manhole at the lowest point and equipped with*su* itaSI pumping apparatus. . The styles and construction of conduits commonly used may be claji sified as follows:1, Filler Type: The pipes are supported on expansion rollers properly supported fr0L the conduit or independent masonry base. The pipes are protected by a split-tile con duit, and the entire space between the pipes and the tile is filled with an insulating filler. Thus the pipes are nested and the insulation between them and the tile effectively prevents circulation of air. The conduit is placed on a bed of gravel or crushed rock from 4 to 6 in. thick, which is extended upward so as to come about 2 in. above the parting lines of the tile. A tile underdrain is placed beneath the conduit throughout the entire length and is connected to sewers or to some othhr point of free discharge. S' . ^52 H <3* 1 Js<2 1.0 Table 6. Flow of Steam Through Pipes Length of Pipe = 240 Diameters Diameteh or Fa's in Inches 2.0 2H 3.0 4.0 s.o 6.0 8.0 10.0 12.0 15.0 orWeight Steam peb Minute in Pounds Losswith One Pound in Pressure 1 1.13 2.04 5.49 9.85 14.8 24.4 45.0 74.2 105 202 329 482 771 1127 10 1.39 2.54 6.82 12.3 18.5 30.3 55.9 92.3 138 248 409 599 958 1404 20 1.63 2.98 8.02 14.4 21.9 35.6 65.7 108 163 295 481 705 1128 1645 30 1.84 3.37 9.07 16.2 24.5 40.2 74.1 122 183 333 542 795 1272 1858 40 2.03 3.71 9.95 17.9 26.9 44.2 81.6 135 202 366 596 874 1388 2089 50 2.19 4.02 10.8 19.4 29.2 47.9 88.3 146 219 397 646 948 1515 2214 60 2.35 4.30 11.5 20.7 31.2 51.3 93.7 156 234 424 691 1014 1623 2372 70 2.50 4.56 12.3 22.0 33.1 54.4 100 166 248 451 734 1075 1722 2517 80 2.63 4.81 12.9 23.2 34.9 57.4 106 175 262 475 774 1135 1814 2653 90 2.76 5.05 13.6 24.3 ' 36.6 60.2 111 183 275 499 812 1192 1893 2782 100 2.88 5.27 14.2 25.4 38.3 62.8 116 191 287 520 848 1243 1990 2908 120 3.10 5.69 15.3 27.4 41.3 67.9 125 207 310 562 915 1342 2148 3138 150 3.38 6.26 16.8 30:2 45.5 74.7- 138 228 341 619 1007 1477 2361 3450 200 3.88 6.96 19.1 34.3 51.5 84.8 156 258 387 703 1144 1677 2685 3919 250 4.33 7.86 21.1 37.9 57.1 93.7 173 285 428 776 1264 1855 2962 4337 300 4.68 8.56 23.0 41.2 62.1 102 188 310 466 845 1376 2019 3226 4717 350 5.03 9.22 24.7 44.5 66.8 110 202 334 501 908 1478 2168 3467 5060 sFrom Marks' and Davis' Tables. *For further data on pipe insulation,.see Chapter 22. 376 Chapter 24--Distkict Heating fPtf&tre'-Vfe'; r' f Tile Type: The insulating material is molded to the inside of a SDlit-tile Sa^tTxh' e pipes are supported on expansion rollers usually. The space between the SSg&jjd the insulating conduit lining may also be filled with an insulating filler The insulation, piping and earth load are supported by the base drain. A few inches Iggfy or crashed rock are placed about the conduit and the base drain. m&mal Insulation Type (Tile Conduit): Each pipe is insulated in the usual way M&y desired type of sectional pipe insulation over which is placed a standard )acket with cemented joints. The pipes are enclosed in a split-tile conduit Sh placed on a bed of crushed rock or gravel from 4 to 6 in. thick. This gravel bed `extended upward so as to come about 2 in. above the parting lines of the tile Under rains are sometimes omitted where this type is used; any water which seeps into the duit being allowed to flow down the bottom of the conduit to the nearest manhole, iios are laid --froamontherofllleororfraomf eeascahnmd athnehsoele, atcocsoordminegptoointht eoftyfrpeee odfisccohnadrgueit uTsehde? I.p-r.a.Ain1?s1a .s<.unipnlipDjoorfrtrteoeddm0bntyhertohflelleocroorfnraodmiueitsitsaen-dlf--o-th-r-e-h-s-aev, eacthceorirdiilnoTMgwetorr npthauerttstyspeet ioni ccounucureut,e,, thus Shotting tIhnesupliapetisoninTdyeppeen(Tdielentoor Cf tohnecrceotendTureitn. ch): A type of construction frequently d*? (. streets, where service connections are required at frequent intervals, the . insulated as described in the preceding paragraph, and are enclosed m a box Sench made either entirely of concrete, or with concrete bottom and specially con- ,tj|e sides and tops. The pipes are supported on roller frames secured in the INsibiiacSfrleeacttteeiod.naalnIdnseunlcaatisoend Type in a (Bituminized Fibre Conduit): Each pipe bituminized fibre conduit. The insulating is individually material is 85 :U1^csnt carbonate of magnesia sectional pipe covering, applied in the usual manner as overhead pipes, except that bands are omitted. After every fifth section of magnesia covering there is applied a short, hollow section of very hard asbestos material in the ibottom portion of which rests a grooved-iron plate, carrying ball-bearings upon which 'the pipe rides when expanding or contracting. This short expansion section is of the e outside diameter as the adjacent 85 per cent magnesia covering. Over the pipe ring and expansion device there are placed two layers of bituminized fibre conduit :witn all joints staggered and the surface of each conduit, finished with liquid cement. --- placed on a bed of crushed rock or gravel, approximately 6 in. deep, and SCthonisndidesureditxrsateainnrsedelpedlaaucdpeinwdgaortndoatopDoaeibnaotsuuito\tf.hi efrecee--ndt--eis-rclhi~;n--aer-goe_fataLhroee,-cpnolnanrcdimeudtitwiwnhheetnhnetrtregenrncachvueisilaboarcckrfuilslehd--e.d \ISffnfcok' beds. PIPE TUNNELS i^Where steam heating lines are installed in tunnels large enough to ^'provide walking space, the pipes, are supported by means of hangers or ^roller frames on brackets or frame racks at the side or sides of the tunnel. Se pipes are insulated with sectional pipe insulation over which is Baced a sewed on painted canvas jacket or a jacket of asphalt saturated bestos water-proofing felt. The tunnel itself is usually built of concrete r (and water-proofed on the outside with membrane water-proofing. Tile ; ..'drains are installed at each side or in the center below the level of the tunnel floor to prevent the building up of static water pressure on the ^v-:o.iu.0tsnideacocfotuhnet ocof nthsetriurcrteiolant.ively high first cost as compared with smaller ; "conduits, walking tunnels are sometimes not installed where provision igtfor the heating lines is the only consideration, but only where required ,;- to accommodate miscellaneous other services, such as for underground -.7?,.passage between buildings. ' STEAM USED PER SQUARE FOOT OF RADIATION PER SEASON y.,? The following factors are used in New York City for the different ^classes of buildings listed. The factors are based on maintaining for ^certain hours 70 deg. inside temperature with a minimum of 0 deg, 377