CLASSIFICATION OF PUMPS AND PUMPING ENGINES.
The simplest division of the subject matter relating to this branch of practical mechanics is that which goes back to the very earliest of times; it is thus:
1. Hand Pumps.
2. Power Pumps.
The names indicate the dividing line between the two. The following are more modern divisions, indicating the method of action distinguishing each:
1. Suction or Lift Pumps.
2. Force Pumps.
3. Suction and Force Pumps.
These again may be reciprocating or rotary. The powers actuating pumps are, in the main, as follows:
1. Manual.
2. Animal.
3. Belts.
4. Water.
5. Wind.
6. Steam.
7. Gas.
8. Electricity.
These various motors give distinct names to general classes, thus, electric pumps, belt pumps, elevator pumps, etc. A sub-division of titles indicating differences in construction are these:
1. Vertical Pumps.
2. Horizontal Pumps, or again
1. Single Acting Pumps.
2. Double Acting Pumps.
The list is still further extended, as pumps vary in design to suit their several uses, and are defined as rope, chain, diaphragm, jet, centrifugal, rotary, oscillating, cylinder. It is with the last named with which this volume has principally to deal; cylinder pumps cause the last given classification, as they are either single or double acting.
A single acting pump does its work through one end of the cylinder or barrel of the pump.
In double acting pumps the motion of the piston in one direction causes an inflow of water, and a discharge at the same time, in the other; and on the return stroke this action is renewed as the discharge end alternately becomes the suction end; the pump is thus double acting.
Finally pumps may be classified with reference to particular uses to which they are specifically adapted by their form and the materials they are required to handle.
Pumps now raise, convey and deliver beer, molasses, acids, oils, and melted asphalt. They also handle such gases as air, ammonia, lighting gas and even oxygen.
In the orderly progress of the contents of the volume, it will be seen that the main subject, occupying many pages with illustrations, is that relating to “Steam pumps;” those having a steam-end and a water-end and which consist of pump and steam-motor combined. An interesting class under Vacuum-pumps will be found, 1, the combined vacuum and feed; 2, the combined vacuum and circulating and, 3, the combined vacuum and refrigerating pumps.
Under Pumping Engines and the Steam Fire Engine will be found a description of the most brilliant and fascinating of modern scientific and mechanical achievements; these two sections relate to hydraulic engineering in its highest development.