Steam, Its Generation and Use

by Babcock & Wilcox Company

Many attempts have been made to use some material other than brick for boiler settings but up to the present nothing has been found that may be considered successful or which will give as satisfactory service under severe conditions as properly laid brickwork.

FOOTNOTES

[75] For methods of determining, see Technologic Paper No. 7, Bureau of Standards, page 44.

[Pg 308]

BOILER ROOM PIPING

In the design of a steam plant, the piping system should receive the most careful consideration. Aside from the constructive details, good practice in which is fairly well established, the important factors are the size of the piping to be employed and the methods utilized in avoiding difficulties from the presence in the system of water of condensation and the means employed toward reducing radiation losses.

Engineering opinion varies considerably on the question of material of pipes and fittings for different classes of work, and the following is offered simply as a suggestion of what constitutes good representative practice.

All pipe should be of wrought iron or soft steel. Pipe at present is made in “standard”, “extra strong”[76] and “double extra strong” weights. Until recently, a fourth weight approximately 10 per cent lighter than standard and known as “Merchants” was built but the use of this pipe has largely gone out of practice. Pipe sizes, unless otherwise stated, are given in terms of nominal internal diameter. [Table 62] gives the dimensions and some general data on standard and extra strong wrought-iron pipe.

[TABLE 62] DIMENSIONS OF STANDARD AND EXTRA STRONG[76] WROUGHT-IRON AND STEEL PIPE Nominal Size Diameter Circumference Internal Transverse Area Length of Pipe in Feet per Square Foot of External Surface Nominal Weight Pounds per Foot External Standard and Extra Strong Internal External Standard and Extra Strong Internal Standard Extra Strong Standard Extra Strong Standard Extra Strong Standard Extra Strong 1⁄8 .405 .269 .215 1.272 .848 .675 .0573 .0363 9.440 .244 .314 1⁄4 .540 .364 .302 1.696 1.144 .949 .1041 .0716 7.075 .424 .535 3⁄8 .675 .493 .423 2.121 1.552 1.329 .1917 .1405 5.657 .567 .738 1⁄2 .840 .622 .546 2.639 1.957 1.715 .3048 .2341 4.547 .850 1.087 3⁄4 1.050 .824 .742 3.299 2.589 2.331 .5333 .4324 3.637 1.130 1.473 1 1.315 1.049 .957 4.131 3.292 3.007 .8626 .7193 2.904 1.678 2.171 11⁄4 1.660 1.380 1.278 5.215 4.335 4.015 1.496 1.287 2.301 2.272 2.996 11⁄2 1.900 1.610 1.500 5.969 5.061 4.712 2.038 1.767 2.010 2.717 3.631 2 2.375 2.067 1.939 7.461 6.494 6.092 3.356 2.953 1.608 3.652 5.022 21⁄2 2.875 2.469 2.323 9.032 7.753 7.298 4.784 4.238 1.328 5.793 7.661 3 3.500 3.068 2.900 10.996 9.636 9.111 7.388 6.605 1.091 7.575 10.252 31⁄2 4.000 3.548 3.364 12.566 11.146 10.568 9.887 8.888 .955 9.109 12.505 4 4.500 4.026 3.826 14.137 12.648 12.020 12.730 11.497 .849 10.790 14.983 41⁄2 5.000 4.506 4.290 15.708 14.162 13.477 15.961 14.454 .764 12.538 17.611 5 5.563 5.047 4.813 17.477 15.849 15.121 19.990 18.194 .687 14.617 20.778 6 6.625 6.065 5.761 20.813 19.054 18.099 28.888 26.067 .577 18.974 28.573 7 7.625 7.023 6.625 23.955 22.063 20.813 38.738 34.472 .501 23.544 38.048 8 8.625 7.981 7.625 27.096 25.076 23.955 50.040 45.664 .443 28.544 43.388 9 9.625 8.941 8.625 30.238 28.089 27.096 62.776 58.426 .397 33.907 48.728 10 10.750 10.020 9.750 33.772 31.477 30.631 78.839 74.662 .355 40.483 54.735 11 11.750 11.000 10.750 36.914 34.558 33.772 95.033 90.763 .325 45.557 60.075 12 12.750 12.000 11.750 40.055 37.700 36.914 113.098 108.43 .299 49.562 65.415

Dimensions are nominal and except where noted are in inches.