Galvanized Sheet Iron Pipes.
—For room cooling, formerly used to a considerable extent was sheet iron pipes. The three-inch galvanized iron spiral riveted pipe is recommended, or where this is not readily obtainable three-inch galvanized iron crimp-joint and soldered seam pipe may be substituted. While not quite so substantial as the spiral riveted pipe, it will, with ordinary care and attention last a long time.
The use of spiral riveted pipe has been found unnecessary, provided No. 24 gauge metal is used in lock seamed pipe. Open-hearth steel, galvanized, is preferable to Bessemer. The writer experienced one failure with the latter.
FIG. 23.—SECTION SHOWING BRINE SALT AND SPRAY SYSTEMS.
Ten different pieces of this pipe ten feet long were capped on either end and submitted to a hydrostatic pressure test; the bursting pressure average of the ten pieces was found to be 146 pounds to the square inch, while some of the samples stood a pressure of over 180 pounds to the square inch. In actual practice the pipe used for this purpose is never subjected to a pressure exceeding forty pounds to the square inch.
Coil Rooms.
—[Fig. 24] shows the end view of the cooler with the detail of the hangers on which the pipe rests. [Fig. 25] shows the end view of one bay with the pipe located and connected.
FIG. 24.—END VIEW OF COOLER; DETAIL OF PIPE HANGERS.