Document MMq539Zq2KE4Q9xEDDjXR3brV

HEATINC VENTILATING AIR CONDITIONING GUIDE 1943 first cost is said to be justified on the basis of longer life expectancy. Wrought-iron pipe may be identified by the spiral line marked into each length, either knurled into the metal or painted on it in red or other bright color. Otherwise, there is little difference in the appearance of wrought iron and steel pipe, although microscopic examination of polished and etched specimens will readily disclose the difference. Cast-Ferrous Pipe. There are now available several types of castferrous metal pipe made of a good grade of cast-iron with or without additions of nickel, chromium, or other alloy. This pipe is available in sizes from in. to 6 in., and in standard lengths of 5 or 6 ft with external and internal diameters closely approximating those of extra strong wrought pipe. Cast-ferrous pipe may 'be obtained coupled, beveled for welding, or with ends plain or grooved for the several types of couplings. It is easily cut and threaded as well as welded. The fact that it is readily welded enables the manufacturers to supply the pipe in any lengths practicable for handling. ' Alloy Metal Pipe. Steel pipe bearing a small alloy of copper or other alloying element and iron pipe bearing a small alloy of copper and molyb denum have been claimed to possess more resistance to corrosion than plain steel pipe and they are advertised and sold under various trade names. Copper Pipe and Fittings. Owing to its inherent resistance to cor rosion, copper and brass pipe have always been used in heating, venti lating, and water supply installations, but the cost with standard dimen sions for threaded connections has been high. The recent introduction of. fittings which permit erection by soldering or sweating allows the use of pipe with thinner walls than are possible with threaded connections, thereby reducing the cost of installations. ' The initial cost of brass and copper pipe installations generally runs higfier than the corresponding job with steel pipe and screwed connections in spite of the use of thin wall pipe, but the corrosive nature of the fluid conveyed or the inaccessibility of some of the piping may warrant use of a more expensive material than plain steel. The advantages of corrosionresisting pipe and Sittings should be weighed against the correspondingly higher initial cost. COMMERCIAL PIPE DIMENSIONS \ The IPS dimensions of commercial pipe universally used at the present time conform to the recommendations made by a Committee of the A.S.M.E. in 1886. Pipe up to 12 in. in diameter is made in certain definite sizes designated by nominal internal diameter which is somewhat different from the actual internal diameter, depending,on the wall thick ness required. There are three weights of wrought iron and steel pipe commonly used, known as standard-weight, extra-strong, arid double extrastrong. Because of the necessity of maintaining the sariie external dia meter in all three weights for the same nominal size, the added wall thickness is obtained by decreasing the. interrial diameter. The term full-weight, when applied to sizes below 8 in., means that the pipe is up to the nominal weight per foot. When applied to sizes between 8 and 12 in., inclusive, it often indicates that the pipe has the heaviest of several wall 346 CHAPTER 18. PIPE, FITTINCS, WELDING thicknesses listed. ' In sizes 14 in. and upward, pipe is designated by its outside, diameter (O.D.) and the wall thickness is specified. While the demands for pipe for the heating and ventilating industry are reasonably well served by the standard-weight and extra-strong pipe, demands for pipe for higher pressures and temperatures in industryresulted in the use of a multiplicity of wall thicknesses for all sizes. Even' in heating installations, the erection of piping by welding was deemed to Table 1. Dimensions of Schedules 30 and 40 and Standard Weight Pipe* External 1 Internal Plain Ends Threads and Couplings | Threads per In. External 1 External Internal Metal Internal Surface Diaketer In. Weight peb Ft, Lb Sise d 3" 1 CmcuMFBBENCE, In. aa a. Tbansvebse Area, Sq In. Length op Pipe, Ft peb Sq Ft i ' OT *3 E Length' op Pipe, Ft Con taining ICuFt Weight op Wateb, La pee Ft 0.405 0369 0.068 0344 0345 27 Q 0.540 0364 0.088 0.424 0.425 18 . Vfl 0.675 0.493 a091 0367 0368 18 M 0.840 0.622 0.109 0.850 0352 14 1372 0.845 1.696 1.144 2.121 1.549 2.639 1.954 0.129 0.229 0358 0354 0.057 0.104 0.191 0304 X 1.050 0324 0.113 1315 1.049 0.133 1IHH 1.660 1.900 1380 0.140 1.610 0.145 2 2375 2.067 0.154 2H 2375 2.469 0.203 3 3300 3.068 0.216 3M .4.000 .3348 0.226 1.130 1.678 2372 2.717 3.652 5.793 7.575 9.109 1.134 14 3399 2389 1.684 I1K 4.131 3.296 2381 im 5.215 4335 2.731 im 5.969 5.058 3.678 im 7.461 6.494 5319 8 9.032 7.757 7.616 8 10.996 9.638 9302 8 12366 11.146 0.866 1358 2.164 2.835 4.430 6.492 9.621 12366 0.533 0364 1.495 2.036 3.355 4.788 7393 9386 4 4300 4.026 0.237 10.790 10389 8 5 5363 ' 5.047 0.258 14.617 14310 8 6 6.625 6.065 0.280 18.974 19.185 8 gc 8.625 8.071 0377 24.696 25.000 8 14.137 12.648 15.904 12.730 17.477 15.856 24.306 20.006 20.813 19.054 34.472 28391 27.096 25356 58.426 51.161 0.072 9.431 14.199 2533.775 0.125 7.073 10.493 1383.789 0.167 5.658 7.748 754360 0350 4347 6.141 473.906 0.025 0.045 0.083 0.132 0333 3.637 4.635 270.034 0331 0.494 2.904 3.641 166.618 . 0375 0.669 2301 2.768 96375 0.65 0.799 2.010 2372 70.733 038 1.075 1.608 1347 1.704 1328 1347 2.228 1.091 .1345 2.680 0.954 1.076 42.913 1.45 30.077 2.07 19.479 3.20 14365 . 439 3.174 0348 0.948 4300 0.686 0.756 5381 0.576 0.629 7.265 0.443 0.473 11312 530 7.198 8.67 4.984 1231 2315 22.18 `8 8.625 7.981 0.322 28354 28309 8' 10 10.750 10.192 0.279 31.201 32.000 8 10C 10.750 10.136 0307 34.240 35.000 8 10 10.750 10.020 036b 40.483 41.132 8 27.096 25373 58.426 50.027 8399 0.443 0.478 33.772 32.019 90.763 81385 9.178 0355 0374 33.772 31.843 90.763 80.691 10.072 0355 0376 33.772 31.479 90.763 78.855 11.908 1355 0381 . 2.878 21.70 1.765 3537 1.785 34.95 1.826 3430 12c 12.750 12.090 0330 43.773 45.000 8` 40.055 37.982 127.676 114.800 12.876 0399 0315 . 1.254 49.70 / 12 12.750 12.000 0375 49.562 50.706 8 40.055 37.699 127.676 113.097 14379 0399 0318 1.273 49.00 1 ^Standard-weight wrought-iron pipe has approximately the same wall thicknesses and weights as contained herein for steel pipe. For exact dimensions, see A merican Standardfor Wrought-iron and Wrought- Sted Pipe, AS.A. B36.10. ^Thicknesses shown in bold face type are identical with thicknesses for Schedule 40 pipe of A.S.A. B36.10. . .. .cSame as Schedule 30, AS.A. B36.10. warrant the use of pipe lighter than standard weight. For these reasons, a Sectional Committee on Standardization of Wrought-iron and Wrought- Steel Pipe and Tubing functioning under the procedure of the American Standards Association was appointed to standardize the dimensions and; materials of pipe. ' The pipe standard recommended by that sectional committee has set; up several schedules of pipe including staridard-weight arid extra-strorig thicknesses which are now included in Schedules 40 and 80, respectively. Dimensions and other useful data for staridard-weight and extra-strong pipe are given in Tables 1 and 2. Table 3 from A.S.T.M. Specifications 347