How Steam is Developed

| January/February 1996

PO. Box 308 W. Frisco Blackwell, Oklahoma 74631

It is not enough for the steam engineer to understand how to start and stop his engine, but he must understand its construction, have a complete knowledge of his boiler, and the fundamental principles of steam, heat, and water.

Almost every engineer knows what steam is, but not all of them can define it. Steam is an elastic fluid resulting from the combination of heat and water. When steam is in contact with water from which it was generated, but without water held in suspension, its temperature corresponds to its pressure and it is known as dry steam.

If it holds water in suspension, it is called wet steam, but if subjected to more heat after being separated from the water that it was generated from, its temperature is then increased without producing a corresponding increase of pressure, it is then called super-heated steam. To put it simply, super-heated steam has a higher temperature than its pressure calls for, and in this condition it is nearly a perfect gas (called gaseous steam).

When we build a fire under a boiler the water directly above the fire is heated first and as a natural consequence rises to the highest point possible (the dome).

The space vacated by this water is filled by water rushing forward and the space vacated by this water is in turn filled by the heated water that arose to the surface.