wheel type; and the third is a geared
pump, which has a horizontal double acting plunger, 36 inches in
diameter, by six foot stroke, driven from the crank of a spur-wheel
shaft.
The spur wheel is 12 feet diameter, 24 inches face, and contains 96
teeth. The pinion engaging with it has 27 teeth, and is fast on the
fly-wheel shaft of a Brown horizontal engine, having a cylinder 18 inches
in diameter, and a stroke of four feet. The steam pressure used is 110
pounds per square inch; and the engine has a Buckley condenser. The pump
valves are annular, of brass, faced with rubber, and close by brass
spiral spiral springs. Their external diameter is six inches, and the
lift is confined to 1/2 inch. There are 91 suction and 91 delivery valves
at each end of the pump. The maximum speed of this pump is twenty-six
double strokes a minute.
The largest of the compound engines is named Ontario, and has a vertical
low pressure cylinder 36 inches in diameter, and an inclined high
pressure cylinder 171/2 inches in diameter; the stroke of both being five
feet. These are inverted over a beam, or rocker; and the pistons are
connected to opposite ends of the same.
The beam attachment of the main connecting rod is made to a pin located
above and midway between the pins for piston connections.
The main center of the beam and the crank shaft have their pedestals in
the same horizontal plane. The throw of the crank is five feet. There are
two differential plunger pumps, having upper plungers 20 inches in
diameter, and lower plungers 33 inches in diameter, with a stroke of 5
feet. These pumps are vertical, and placed beneath the engine bed-plate,
to which they are attached by strong brackets. The pump under the low
pressure cylinder is worked directly from its cross-head by an extension
of the piston rod. The other pump is worked by a trunk connection from
the opposite end of the beam. The radius of the beam is but fifty inches,
but the connections to it are made very long by links.
The lower plungers work through sleeves in diaphragms located in the
center of the pumps. In these diaphragms, the openings for the delivery
valves are made. These valves are similar in construction to those
previously described for the horizontal plunger pump. Their diameter,
however, is but 51/4 inches, instead of 6 inches, and there are 72 suction
and 72 delivery valves for each pump. It will readily be seen that the
action of these pumps is similar to th
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