PRINCIPLES OF NAVAL ENGINEERING 



DOME 



LOADING 

 CHAMBER 



SEPARATION 

 PLATE 

 ORIFICE 



DIAPHRAGM 

 PLATE 



DOME 

 NEEDLE 

 VALVE 



DOME 



SEPARATING 



PLATE 



PLUG 



{FOR EXTERNAL 



CHARGING) 



CHARGING 

 CONNECTION 



RELIEF 

 VALVE 



ACTUATING 

 CHAMBER 



BODY 

 NEEDLE 

 VALVE 



DIAPHRAGM 



PRESSURE 

 EQUALIZING 

 ORIFICE 



DIAPHRAGM 

 PLATE 

 SPRING 



OUTLET 



VALVE 

 SEAT 



VALVE 



VALVE 

 SPRING 



CAGE 



47.60 



Figure 14-21.— Pneumatic pressure controlled reducing valve for low temperature service 



diaphragm. This action forces the reverse-act- 

 ing valve off its seat. The pressure entering 

 the regulator is then permitted to flow through 

 the open valve into the reduced pressure line. 

 A large pressure equalizing orifice transmits 

 this pressure directly to the underside of the 

 diaphragm. When the delivered pressure ap- 

 proximates the loading pressure in the dome, 

 and the unbalanced forces are equalized, the 

 valve is closed. With the slightest drop in 

 delivered pressure, the pressure charge in the 



dome instantly forces the valve open, thus allow- 

 ing air to pass through the valve and maintain the 

 outlet pressure relatively constant. 



The pneumatic pressure controlled reducing 

 valve for high temperature service (fig, 14-22) 

 operates in much the same way as the valve for 

 low temperature service, except that the valve 

 for high temperature service.is designed in such 

 a way as to keep heat from the hot fluid from af- 

 fecting the gas in the loading chamber. The 



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