User Manual for a Steam Engine

Steam is reliable and renewable!

Big image

Parts of a Steam Engine

  1. A fire where the coal burns.
  2. A boiler full of water that the fire heats up to make steam.
  3. A cylinder and piston (steam from the boiler is piped into the cylinder, causing the piston to move first one way then the other)
  4. A machine attached to the piston (a water pump, factory machine or even a giant steam locomotive)
Big image

Step 1

Inside the locomotive cab, load coal into the firebox (1). The fire heats up the boiler—the "giant kettle" inside the locomotive. The boiler (2) produces steam under high pressure. The boiler is a big tank of water with dozens of thin metal tubes running through it. The tubes run from the firebox to the chimney, carrying the heat and the smoke of the fire with them (shown as white dots inside the tube). This arrangement of boiler tubes means the engine's fire can heat the water in the boiler tank much faster, so it produces steam more quickly and efficiently. The water that makes the steam either comes from tanks mounted on the side of the locomotive or from a separate wagon called a tender, pulled behind the locomotive (the tender also carries the locomotive's supply of coal.)

Step 2

The steam generated in the boiler flows down into a cylinder (3) just ahead of the wheels, pushing a tight-fitting plunger, the piston (4), back and forth. A little mechanical gate in the cylinder, known as an inlet valve lets the steam in. The piston is connected to one or more of the locomotive's wheels through a kind of arm-elbow-shoulder joint called a crank and connecting rod (5).

Step 3

As the piston pushes, the crank and connecting rod turn the locomotive's wheels and power the train along (6). When the piston has reached the end of the cylinder, it can push no further. The train's momentum (tendency to keep moving) carries the crank onwards, pushing the piston back into the cylinder the way it came. The steam inlet valve closes. An outlet valve opens and the piston pushes the steam back through the cylinder and out up the locomotive's chimney (7). The noise that a steam engine makes and its puffs of smoke are a result of the piston moving back and forth in the cylinder. There's a cylinder on each side of the locomotive and the two cylinders fire slightly out of step with one another to ensure there's always some power pushing the engine along.

Resources and