PRINCIPLES OF NAVAL ENGINEERING 



CONDENSATE 

 RETURN LINES 



SUPERHEATER 

 OUTLET 



Figure 11-32.— Jerguson superheater steam flow indicator. 



98.96 



systems, are controlled by one variable only— 

 namely, the water level variation in the steam 

 drum. Hence single-element regulators are not 

 able to compensate for swell and shrink. 



Single-element regulators are intended pri- 

 marily for keeping the boilers supplied with 

 feed water in battle or under other conditions 

 when manual feeding of the boilers might be- 

 come difficult or impossible. These regulators 

 must be cut in immediately when General Quar- 

 ters is sounded. They may also be used at 

 other times, and in fact should be used fre- 

 quently enough to keep them in good working 

 order and ready for use under emergency con- 

 ditions. 



Single-element regulators can control the 

 water level within acceptable limits under rela- 

 tively steady steaming conditions, but not under 

 severe maneuvering conditions. Since complete 

 reliance cannot be placed on the single-element 

 regulator, a checkman must remain on station 

 and be ready to take manual control if necessary 

 when the single-element regulator is in use in 

 other than emergency conditions. 



A single-element automatic feed water regu- 

 lator is shown in figure 11-37. An inner tube, 

 enclosed by a generator, is connected to the 

 boiler steam drum through valves A. and B. 

 Thus the water level in the inner tube is depend- 

 ent upon the water level in the steam drum. 



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