CANE SUGAR. 



Th.6 Centrifugal Machine. A centrifugal machine consists 

 essentially of a vertical cylindrical perforated basket, which is caused to 

 revolve at a high rate of speed ; within the perforated basket is fixed a wire 

 gauze strainer, containing from 400 to 500 perforations per square inch. The 

 revolution of the basket throws the magma of crystals and molasses against 

 the side of the basket ; the molasses and a portion of the crystals pass through 

 the gauze, and the great portion of the crystals are retained ; without the 

 perforated basket is a casing which catches the molasses and directs them by a 

 spout into the gutter. 



Types of Centrifugals. Centrifugals were perhaps introduced 

 into the sugar industry in 1849, by Dubrunfaut, and now a large number of 



FIG. 201. 



types are to be found ; mainly they fall into two classes, fixed bearing pattern 

 and suspended pattern ; again they may be divided into under and over-driven 

 machines, or according to the method of driving, direct coupled, friction cones, 

 belt, electric, or water drive. 



Fixed Bearing Friction Cone Machine. In Fig. 201 is 

 shown a view of this type of machine ; / is the spindle revolving in two 

 brasses, i and /, the lower brass i being fixed in the bottom of the monitor 

 outer casing k and the upper one j in the cross piece of the frame h, which is 

 supported on and bolted to the outer case ; the basket I is secured to the 

 spindle by the nut g, screwed down on the cone m, which rests on the bottom 

 of the basket ; a collar n on the spindle prevents any downward movement. 



372 



