N
|30|
8 in eighths of inches, or N
240 inches.
The upper fifteen to eighteen inches of the barrel must be left for steam room.
OF THE DIAMETER OF BARREL.
357. To find the diameter of a barrel to contain a given number of tubes,
| Represent the inside diameter of boiler by | D, |
| Diameter of one tube | d, |
| Clearance between tubes | c, |
| Number of tubes | n, |
| Sectional area of boiler, in inches | A, |
| Water section, in inches | B, |
we shall have as the area of water room per tube,
(d + c)2,
and the whole area of water room,
(d + c)2 × n,
the whole section of the barrel,