_The eccentrics_—six in number—are set at 60°, and an even strain on the belt at all points of the stroke is thus obtained, and connecting both discharges together insures a steady flow without shock. Where light duty only is required, these pumps are made without gears to run with the belt over pulleys. Fig. 212 represents _a single acting triplex plunger pump_ actuated by a belt over a tight and loose pulley. The principal characteristic of this pump is the long connecting rods. These have at their upper ends regular connecting rod straps with brasses fitted to them and adjusted by wedges and set screws. At the plunger or lower ends of these rods bronze bushings and steel pins are used. These pumps are largely employed for pumping semi-liquids such as tar, soap, mud, tan-liquor, oils, chemicals, sewage, etc. The teeth of the pinion and the meshing part of the two gears are protected by _a shield_ to prevent clothing being caught or parts of the body from being injured. For these various materials different valves are necessary to be used each suited to the substance to be elevated or conveyed. The removal of one cover, in this pump, exposes all the discharge valves and a plate uncovers each of the three groups of suction valves, as shown. The suction pipe may be attached at either end of the suction chamber while the discharge pipe may be connected with one or both ends of the discharge chamber. The pump here represented has barrels 8-inch in diameter by 10-inch stroke. The air chamber is very large in proportion to the pump. TABLE. ===============+=============+==================+======+========== PLUNGERS |Capacity one | SIZES OF PIPE | | Tight ---------------+Revolution of+--------+---------+Geared|and Loose Diameter Stroke| Crank Shaft |Suction |Discharge| | Pulleys ---------------+-------------+--------+---------+------+---------- 4 in. 4 in.| 0·65 gals. | 3 in. | 3 in. |5 to 1|20 × 3 in. 4 „ 6 „ | 1· „ | 3 „ | 3 „ |5 to 1|20 × 3 „ 5 „ 6 „ | 1·5 „ | 4 „ | 4 „ |4 to 1|20 × 4 „ 5 „ 8 „ | 2· „ | 4 „ | 4 „ |4 to 1|20 × 4 „ 7 „ 8 „ | 4· „ | 5 „ | 5 „ |4 to 1|30 × 5 „ 8 „ 10 „ | 6·5 „ | 6 „ | 6 „ |5 to 1|36 × 6 „ 8 „ 12 „ | 7·8 „ | 6 „ | 6 „ |5 to 1|36 × 6 „ ---------------+-------------+--------+---------+------+---------- _The Deane single acting triplex power pump_ is shown in Fig. 213. Pumps of this type are used for general service in places where a large quantity of water is to be obtained in a short time and delivered under high pressure; they are adapted for tank service, water works, boiler feed, etc. [Illustration: FIG. 213.]