MILK-PLAXT OrEKATTON. 



17 



this course is followed, the empty bottles should be inverted in the 

 cases so as to avoid the drip from the next case above. 



At medium-sized or largo plants automatic pressure washers are 

 commonly used. (See Fig. 13.) These machines also give the 

 cases a washing and steaming which keeps them in good condition. 

 Wlicre these automatic washers are used care must be taken to see 

 that all the jet openings are working at all times and that the solu- 

 tions in the various tanks are kept at the proper strengths and 

 temperatures. The temperature in the first tank should not be 

 above 100° or 120° F. at the highest, so that the bottles will not be 

 broken. Each succeeding tank should be a little hotter until the 

 final tank, which should be near the boiling point. 



I'lG. 14. — Automatic bottle washer showing pnmps; thermometers indicate the temperatures in the 



various tanks. 



In small machines of this type with only two or tliree tanks, 

 the increase in temperature of the water in the various tanks is 

 more sudden. Table 5 gives temperatures observed in the various 

 tanks at several plants. (See Fig. 14.) 



Table 5. — Tcmperalurcs observed in the various tanks of automat ic-pressure washers 



at several plants. 



riant No. 



Num- 

 ber of 

 tanks. 



Temperatures of the various solutions in tanks. 



Tankl. 



Tank 2. 



Tank 3. 



Tank 4. 



Tank o. 



1 



5 

 4 

 4 

 3 

 3 



120 

 90 

 UX) 



no 



90 



'F. 

 140 

 120 

 120 

 150 

 140 



°F. 

 160 

 160 

 140 

 ISO 

 180 



'F. 

 ISO 

 200 

 170 



"F. 

 200 



2 





3 





4 





5 













28554°— 23— Bull. 973- 



