Mance: Quarry Industry of Southern Indiana 75 



resulting temperature of the latter is higher than can be obtained 

 with closed heaters, in which all heat transfers must be effected 

 thru metal partitions that offer resistance to such transfer. One 

 advantage of the closed feed-water heater is the fact that the 

 boiler-feed pump can be eliminated and an injector can be placed 

 in the pipe leading to the heater thus feeding the boiler thru the 

 heater. The saving will be the difference between the cost 

 of a feed pump and an injector. In most quarry and mill service 

 the open heater will be the best adapted to the work. 



In the selection of an open heater the following considerations 

 should be taken into account: 



1. There should be ample arrangements for the storage of 

 the heated waters until withdrawn by the feeding pump; there 

 should be the necessary arrangement of pipes to keep the water 

 hot until it is used. 



2. A separator or separating chamber for the removal of 

 the oil contained in the exhaust steam must be an integral part 

 of the heater. 



3. The reservoir should be provided with blow-off, over- 

 flow, and water glass. The feed pump connection should be a 

 few inches above the blow-off. 



4. There should be a large heating and purifying chamber 

 containing pans, trays, or trough, so arranged that the cold feed 

 water must flow over all of them in order that the exhaust steam 

 may come in contact with the water on every tray. The trays 

 should be easily removable for ready cleaning. 



5. All grease should be removed from the water. 



6. A filter bed should be provided thru which the water 

 must pass after it has been heated. 



7. Suitable cut-out valves should be supplied to the water 

 lines. 



The general proportions of open feed- water heaters vary 

 greatly with the different arrangements of the storage chamber 

 and the trays and pans, so that it is difficult to give a definite 

 size of heater to be used with any particular boiler capacity. 

 There is a tendency among manufacturers of feed-water heaters 

 to overrate the capacity of their heaters. Care should therefore 

 be exercised in buying, to make sure of the proper size of heater 

 for the boiler equipment of the plant. Professor Gebhardt in Steam 

 Power Plant Engineering (first edition, p. 425), gives the following 



