

CENTBIFUGAL PUMPS 



Where the water to be pumped contains grit, as is usual for example in 

 colliery workings, the leading edges of such vanes are apt to be badly worn 

 or bent from their original position, in which case the efficiency of working 

 is seriously affected. To obviate this difficulty a design of single impeller 

 high-lift pump, in which these multiple vanes are absent, has been evolved 



FIG. 308. Worthington Single Impeller High Lift, Pump. 



by the Worthington Pump Co., and is illustrated in Figs. 307 and 

 308. In this pump, designed to deliver 2,500 gallons per minute at 

 1,170 revolutions per minute against 300 feet head, the combined efficiency 

 of pump and motor attained, on test, a maximum value of 73'8 per cent, 

 the corresponding pump efficiency being approximately 80 per cent. 1 



1 Engineering, Feb. 5, 1909. By courtesy of Messrs. The Worthington Pump Co. 



