CLASSIFICATION OF STEAM ENGINES

A steam engine is of the reciprocating type, in which the piston moves to-and-fro in the cylinder due to the force applied by the expansion of steam. The reciprocating steam engines may be classified as follows:

1. According to class of service:
   1. Stationary
   2. Marine
   3. Locomotive
   4. Pumping or hoisting
2. According to speed:
   1. Low speed: below 125 rpm
   2. Medium speed: 125 to 300 rpm
   3. High speed: above 300 rpmNote that the speed of the engine means speed of the crankshaft.
3. According to arrangement of cylinders:
   1. Horizontal
   2. Inclined
   3. Vertical
4. According to type of valve design:
   1. Simple plate valve
   2. Balance plate valve
   3. Piston valve
   4. Riding cut-off valve
   5. Poppet valve
   6. Corliss valve
5. According to method of governing:
   1. Manual or automatic governing
   2. throttle or cut-off governing
   3. Centrifugal or inertia type governor
6. According to type of exhaust:
   1. Condensing type
   2. Non-condensing type
7. According to steam condition:
   1. High or low pressure
   2. Saturated or superheated
8. According to the action of steam upon the piston:
   1. Single acting
   2. Double acting
9. According to the nature of expansion:
   1. Expansive engines
   2. Non-expansive engines
10. According to the range of expansion of steam:
    1. Simple steam engine
    2. Compound steam engine