Steam locomotive nomenclature
Steam locomotive nomenclature is a listing of the components found on a Steam Locomotive.
Fig. 1: Steam Locomotive
Fig. 2: Steam Locomotive and Tender
The following components appear on the illustrations shown above.
- Boiler — A water container that is brought to a boil by hot gases passed through long tubes, thereby producing steam.
- Fire box — A box to contain the fire that is used to heat the boiler.
- Smoke box — The drum which draws through hot gases by means of a partial vacuum produced by released steam, further heating the boiler.
- Steam chest — An area that is used to collect steam for release into the cylinder by valves.
- Cylinder — A hollow device that converts steam energy into mechanical energy.
- Cross head — A block which holds the axle connecting the piston rod to the main rod.
- Guides — These guide the piston rod in and out of the cylinder. Also known as slide bars.
- Piston rod — A rod that connects the piston in the cylinder to the cross-head axle.
- Valve stem — A rod attached to the valve for moving it during engine operation.
- Link
- Reverse lever — A lever within the cab that controls the direction of travel and the timing of the valve. Also called a "johnson bar".
- Reach rod — This rod links the reversing actuator with the valve gear.
- Tumbling shaft
- Rocker arm
- Eccentric rod
- Frame
- Equalizing bars
- Springs
- Pedestal
- Injector
- Boiler check
- Steam drum — An expansion where water is separated from the heated steam.
- Filling funnel — A funnel for adding water.
- Sand box — A container for holding sand used to improve traction.
- Cab — A compartment for controlling the engine and feeding the fire box.
- Air pump
- Foot board
- Hand rail
- Pilot truck — Wheels at the front that helped guide the locomotive.
- Trailing truck
- Drivers — The wheels that deliver locomotive power to the rails.
- Main rod — A steel arm that converts the horizontal motion of the piston into a rotation motion of the Driver. Also called the connecting rod.
- Side rods
- Tender — A container that holds combustible fuel for the fire box.