===========+===========+========+=================
| | | Horse-power
| | | of Boiler based
| | | on 45 pounds of
| | | water per hour,
| | | which this
Diameter of|Diameter of| Length | pump will
Steam | Water | of | supply at
Cylinders | Pistons | Stroke | slow speed.
-----------+-----------+--------+-----------------
4-1/2 | 2-3/4 | 4 | 170
5-1/4 | 3-1/2 | 5 | 280
6 | 4 | 6 | 470
| | |
6 | 4-1/2 | 6 | 590
7-1/2 | 5 | 6 | 670
9 | 6 | 6 | 960
| | |
7-1/2 | 4-1/2 | 10 | 800
9 | 6 | 10 | 1400
10 | 7 | 10 | 2200
| | |
12 | 8-1/2 | 10 | 3200
12 | 9-1/4 | 10 | 3800
14 | 10 | 15 | 4800
-----------+-----------+--------+-----------------
===========+===========+========+======================================
| | | Sizes of Pipes for
| | | Short Lengths
| | | To be enlarged as
| | | length increases.
| | +-------+---------+---------+----------
Diameter of|Diameter of| Length | | | |
Steam | Water | of | Steam | Exhaust | Suction | Delivery
Cylinders | Pistons | Stroke | Pipe | Pipe | Pipe | Pipe
-----------+-----------+--------+-------+---------+---------+----------
4-1/2 | 2-3/4 | 4 | 3/4 | 1-1/4 | 2 | 2
5-1/4 | 3-1/2 | 5 | 1 | 1-1/2 | 2-1/2 | 2-1/2
6 | 4 | 6 | 1-1/2 | 2 | 4 | 3
| | | | | |
6 | 4-1/2 | 6 | 1-1/2 | 2 | 4 | 3
7-1/2 | 5 | 6 | 1-1/2 | 2 | 5 | 4
9 | 6 | 6 | 2 | 2-1/2 | 5 | 4
| | | | | |
7-1/2 | 4-1/2 | 10 | 1-1/2 | 2 | 4 | 3
9 | 6 | 10 | 2 | 2-1/2 | 5 | 4
10 | 7 | 10 | 2 | 2-1/2 | 6 | 5
| | | | | |
12 | 8-1/2 | 10 | 2-1/2 | 3 | 6 | 5
12 | 9-1/4 | 10 | 2-1/2 | 3 | 6 | 6
14 | 10 | 15 | 2-1/2 | 3 | 8 | 6
-----------+-----------+--------+-------+---------+---------+----------
===========+===========+========+=========================
| | |
| | | Approximate Space
| | | Occupied
| | | Inches
| | +--------+-------+--------
Diameter of|Diameter of| Length | | |
Steam | Water | of | Height | Depth | Width
Cylinders | Pistons | Stroke | | |
-----------+-----------+--------+--------+-------+--------
4-1/2 | 2-3/4 | 4 | 38 | 18 | 23
5-1/4 | 3-1/2 | 5 | 46 | 22 | 29
6 | 4 | 6 | 50 | 23 | 32
| | | | |
6 | 4-1/2 | 6 | 50 | 23 | 32
7-1/2 | 5 | 6 | 54 | 28 | 33
9 | 6 | 6 | 57 | 27 | 36
| | | | |
7-1/2 | 4-1/2 | 10 | 66 | 28 | 33
9 | 6 | 10 | 68 | 27 | 36
10 | 7 | 10 | 77 | 34 | 40
| | | | |
12 | 8-1/2 | 10 | 86 | 39 | 44
12 | 9-1/4 | 10 | 86 | 39 | 44
14 | 10 | 15 | 110 | 36 | 50
-----------+-----------+--------+--------+-------+--------
A notable feature in this pump is the location of the exhaust passage;
_this opening is underneath the cradle_—or the part that the pump rests
upon—just forward of the steam cylinders. The flanges of the steam end
and cylinders and the steam chest cover have been made heavier than the
regular and strengthened to withstand the higher pressures.
Fig. 305 is a sectional view of a larger size duplex pump than the one
shown in Fig. 302. The plunger, B, packing is identical, but the number
of water valves is double; access for cleaning the suction chamber, C,
is had by removing the hand hold plate at the side and in the center.
The discharge valves are reached through the hand hold at D.
[Illustration: FIG. 305.]