Fig. 213.
The pillar, or column design of frame is employed in this pump which secures great strength with the least weight of material, and at the same time is accessible for adjustment or repairs. The bearings for both the steel shafts are unusually long, which reduces the pressure per square inch below the factor of safety and increases the durability. The crankpins are set 120 degrees with one another so that the strokes successively overlap, which promotes an easy flow of water through the delivery pipe. The crank shaft is of the composite design, the center crank pin is of equal diameter and forming a part of the shaft, with discs and crank pins attached to each end by shrinking fits and keys. Either disc, crank, or their crank pins, can be duplicated without sacrificing any other part, which in itself is a great advantage.
The connecting rods have solid ends with adjustable boxes, with adjustment by means of wedge and screws. The brasses are lined with a special anti-friction metal bored to exact size.
The crossheads are of the box design with adjustable shoes having large wearing surfaces in bored guides. These guides are secured to the frame by studs and nuts.
The plungers are outside packed, the cylinders are submerged, thus keeping the pump primed at all times. The plungers are bolted to the crossheads and are readily removed when necessary. The cylinders are single acting and are cast separate from the base and other parts of the machine, so that repairs can be made at small cost, and, furthermore, should it be desirable to use the pump for moving liquids which would be injurious to cast iron, cylinders of other metals are substituted. The water chest is cast separate from the cylinders and is provided with large handholes, affording easy access to the interior and to the valves for inspection and cleaning. The handholes are located so that one valve may be removed independent of the others.
Improved grease cups are placed on all the bearings. This pump is very popular with the users of power driven pumps and is generally selected for high pressures and for hot or gritty water. Its simplicity of design and construction, together with the convenient arrangement of working parts, renders it desirable in isolated places where little attention is given to any kind of pumps.
Fig. 214.