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Boiler Operator's HandbookOperators will find plenty of help and guidance in Ken's boiler operator's handbook published by Fairmont Press. In writing it he made every effort to avoid the normal criticism of operator's handbooks. This one was written by a boiler operator for boiler operators, even though the author is an engineer. Every effort to address the operation of the plant not its engineering; you of course, will be the final judge of that. The book includes the typical graphs and charts but tuned to boiler operator's needs. There's a steam table but the pressures are listed in gage pressure, not absolute. That's just one of the ways Ken has tried to make this book operator friendly. Save 10%, the Handbook is available by using Order Code 0532 at AEE Center |
![]() If you've attended one of Ken's training classes you have one of these pocket size steam tables. If you don't, send Ken a stamped, self addressed envelope and he'll return it with one of these cards inside. These steam tables are designed for operators in the Baltimore Metropolitan area because they use inches of vacuum and gage pressures (psig) instead of absolute pressures (psia) that are used on engineer's steam tables. If you happen to be operating a boiler at a site with an elevation over 500 feet the error is significant and you should obtain engineer's steam tables and learn how to correct for atmospheric pressure to get more accurate values. Over 2,000 feet these operator tables are so inaccurate that you shouldn't try using them. | |
The values for heat in the steam tables are called "enthalpy" and are based on the contention that enthalpy is zero in water at 32 degrees Farenheit. We could remove heat from water at that temperature but we're into steam and there's no sense in using a lower value of zero. Recall the rule that a Btu is the amount of heat necessary to raise the temperature of water one degree Farenheit? A close look at the tables reveals why we have them; water doesn't follow simple rules. The rule only applies between 69 and 70 degrees Farenheit. Steam tables come in two forms, the card is a saturated steam table and only shows saturation conditions where steam and water are in close contact with each other and the steam and water temperatures are the same. For each pressure there is a corresponding temperature at which water boils. If you only know the pressure you can determine the temperature using the steam table; conversely, if you know the temperature you can tell the steam pressure. If you add any heat to the mixture some of the water is converted to steam and if heat is removed some of the steam will condense to water. In either direction it takes latent heat (the second column from the right) to convert a pound of the water to steam and that much is given off to convert a pound back to water. The specific volume (cubic feet per pound) for the liquid and the steam are listed so you can calulate the change in volume at the saturated conditions. Divide the values into one to get pounds per cubic foot. Once steam is separated from water its temperature rises just like air. The difference is a varying specific heat, although you could use a specific heat of 0.5 to get a rough idea, more accuracy can be achieved using the superheated steam table. Some typical values for superheated steam are included with the tables you can download from here. These tables include the more common operating pressures and temperatures. For more accuracy you should seek out a copy of Keenan & Keyes steam tables. | |
Download Steam Tables for Operators Return to the top |
Download Square Root Curve |
Download Square Root to Linear Chart |
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![]() This is another non-linear relationship that Boiler Operators should be aware of. Excess air and oxygen content of the flue gas are not directly proportional. To determine excess air quantity from an oxygen reading follow a vertical line from the oxygen reading on the bottom axis to the curve then a horizontal line to the left axis to read the quantity of excess air. Why doesn't the curve include values above 16% O2? Because values that high are ridiculous for boiler operation. If you're operating a gas turbine or reciprocating engine you would need a chart for higher values but the stack losses for values over 6% oxygen are excessive for a boiler. Download Excess Air / Oxygen CurveReturn to the top |