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Indiana University Studies 



9. Be careful to keep the pump well packed and the packing 

 even. 



It would be more economical for the pump user to employ 

 a power pump, where electrical energy is available, because the 

 steam-end pump at its best is very wasteful of steam. An engine 

 that consumed over 35 pounds of steam per horse-power hour 

 would be considered very inefficient, but the ordinary steam-end 

 pump with its slide valves taking steam under full pressure 

 thruout the entire stroke, and exhausting at full pressure, uses 

 over 100 pounds of steam per horse-power hour. A belted 

 power pump takes less than one-fourth the power necessary for a 

 steam-end pump. 



The use of feed-water heaters is one of the most economical 

 practices connected with power plant operation. The heat 

 utilized in heating the feed water for a boiler is a clear gain and 

 in the course of a year represents a large part of the cost of coal. 

 The boiler water can be heated to 200 or even 210 degrees Fahren- 

 heit by means of the exhaust steam from the engine and pumps. 

 At the present time the waste heat in the exhaust steam from the 

 engines is used, but a large amount of heat is being lost in the 

 exhaust steam from the pumps. 



Altho feed-water heaters act to a great extent as water purifiers, 

 their greatest advantage lies in their ability to make use of a 

 certain amount of heat that would otherwise be a total loss. For 

 every increase of 10 degrees in the temperature of the feed water 

 there is a gain of approximately 1 per cent in the saving of 

 coal. In other words, at least 12 per cent of the heat of the 

 coal can be utilized in first-class heaters. For every pound of 

 exhaust steam utilized in the feed-water heater 6 pounds of 

 feed water can be heated from a temperature of 50 degrees Fahren- 

 heit to a temperature of 210 degrees. In addition to saving a 

 large portion of the heat generated under the boiler, the smaller 

 the difference in temperature between the steam and the feed 

 water, the less will be the strain on the boiler shell on account of 

 unequal expansion and contraction, and thus the life of the boiler 

 will be lengthened. The cost of water-heaters is a very insignifi- 

 cant item when compared to the saving effected. In fact, it has 

 been said that 6 boilers with the best methods of feed-water heat- 

 ing will furnish as much steam as 7 boilers of the same size heating 

 their own supply of water. The open heater is more efficient than 

 the closed heater, because the steam which furnishes the heat 

 comes into intimate contact with the water to be heated, and the 



