Chapter 16. -AUXmiARY STEAM TURBINES 



SECTION THRU 

 BLADING 



SECTION "A-A" 



Figure 16-4.— Auxiliary turbine for main condensate pump, feed booster pump, 



and lubricating oil service pump. 



47.9X 



and governors.^ Pressure lubrication systems 

 for auxiliary turbines do not provide lubrication 

 for governor linkages or— except on some turbo- 

 generator sets— for flexible couplings; these 

 parts of the unit must be lubricated separately. 



2 Some very small commercially designed auxiliary 

 turbines have self-oiling bearings instead of pressure 

 lubrication systems. A self -oiling bearing has one or 

 two rings which hang on the turbine shaft and revolve 

 with it, although at a slower rate. On each revolution, 

 the rings dip into an oil reservoir and carry oil around 

 to the upper part of the bearing shell. 



A pressure lubrication system requires a 

 lube oil pump. As a rule, the lube oil pumps used 

 for auxiliary units are positive-displacement 

 pumps of the simple gear type, as discussed in 

 chapter 15 of this text. The lube oil pump is gen- 

 erally installed on the turbine end of a forced 

 draft blower unit, but may be on either the driv- 

 ing or the driven end of pump units. The lube oil 

 pumps for turbogenerators are usually driven by 

 auxiliary gearing connected to the low speed gear 

 shaft. Some forced draft blowers use a centrif- 

 ugal pump, supplemented by a viscosity pump, for 

 lubrication of the unit; this type of lubrication 

 system is peculiar to forced draft blowers and is 



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