

DAIRYING 43 





Clogging of the separator bowl is usually indicated by a 

 change in the thickness of the cream. When the bowls become so 

 filled with slime that milk cannot pass through the skim milk 

 tubes, it must leave the bowl through the cream tube, and con- 

 sequently the cream becomes thin by the milk passing out the 

 cream spout. 



Factors Influencing the Efficiency of Cream Separators 



1. The speed of the separator bowl. 



2. The temperature of the milk, and method of heating milk. 



3. The richness of the cream separated. 



4. The amount of milk skimmed per hour. 



5. Sour or clotted milk. 



6. Cream outlet becoming clogged. 



7. Bowl not clean. 



8. The steady, smooth running of the bowl at full speed and 

 the uniformity with which the bowl speed, the milk feed, and the 

 temperature of the milk recommended by the manufacturer are 

 maintained. 



1. The Speed of the Separator Bowl 



299. The manufacturers determine, by careful tests, the safe 

 speed at which their separator bowls may be run. This will vary 

 with their diameter, as it has already been shown that the cen- 

 trifugal force exerted on the walls of a bowl increases as the 

 square of the diameter ; a ten inch bowl may be run at a speed of 

 6000 revolutions per minute ; and one three inches in diameter 

 may safely make 20,000 revolutions per minute. The speed recom- 

 mended by the manufacturer ought to be known by each user 

 of a cream separator, and the speed should be maintained when- 

 ever the machine is used for skimming milk. If run below speed 

 there may be an unnecessary loss of butter fat in the skim milk, 

 and too high speed may be the cause of serious accidents. In- 

 creasing the speed will sometimes improve the skimming done by 

 some separators, but there is more or less danger from such a 



