A saturated steam table is an indispensable tool for any engineer working with steam. It's typically used to determine saturated steam temperature from steam pressure, or the opposite: pressure from saturated steam temperature.
In addition to pressure and temperature, these tables usually include other related values such as specific enthalpy (h) and specific volume (v).
The data found in a saturated steam table always refers to steam at a particular saturation point, also known as the boiling point.
Saturation point is the point where water (liquid) and steam (gas) can coexist at the same temperature and pressure.
Because H2O can be either liquid or gas at its saturation point, two sets of data are required: data for saturated water (liquid), which is typically marked with an "f" in subscript, and data for saturated steam (gas), which is typically marked using a "g" in subscript.
Notations used are:
- P = Pressure of the steam/water
- T = Saturation point of steam/water (boiling point)
- vf = Specific volume of saturated water (liquid).
- vg = Specific volume of saturated steam (gas).
- hf = Specific enthalpy of saturated water (energy required to heat water from 0°C (32°F) to the boiling point)
- hfg = Latent heat of evaporation (energy required to transform saturated water into dry saturated steam)
- hg = Specific enthalpy of saturated steam (total energy required to generate steam from water at 0°C (32°F)).