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HYDKAULICS AND ITS APPLICATIONS 



Some modern types of construction of the compound high-lift pump are 

 indicated in Figs. 309 to 317. 



Fig. 309 shows the construction adopted by Messrs. Sulzer Bros. Here 

 the impellers are mounted in pairs back to back, the flow through these 



FIG. 309. Sulzer Sextuple Compound High Lift Pump. 



being in opposite directions. By this construction each pair of impellers 

 is in balance as regards end thrust. The pump is fitted with diverging 

 guide passages, curved vanes, and a vortex chamber, while Fig. 310 shows 



the type of water-sealed stuffing box and 

 water-cooled bearing adopted by the makers. 

 The Buffalo high-lift pump (Figs. 311 

 and 312) is built on somewhat similar lines 

 also having impellers mounted in pairs, 

 while in the Mather-Eeynolds pump (Fig. 

 313), constructed with a double inlet to 

 each propeller, the guide passages and 

 curved vanes are retained, while the vortex 

 chamber is omitted. The construction is 

 thus simplified without seriously affecti 

 the efficiency, a quadruple pump of this 

 type giving efficiencies up to 75 per cent, 

 when delivering 1,000 gallons per minute against 320 feet head. 



The foregoing arrangement of impeller, however, necessitates compli- 

 cated and tortuous connecting passages, and a simpler construction is 

 obtained where, as shown in Figs. 314 to 318, impellers, each having a 

 single inlet, are used. This system has the further advantage that any 

 odd number of impellers may be used. On the other hand, with the single 



FIG. 310. Water-Sealed Stuffing- 

 box for Sulzer Pump. 



