EXHAUSTING AND SEAMING 



In California most of the plants employ steam boxes for exhausting 

 followed by standard seaming machines. Time of cans in the exhaust box 

 varies from 1 to 5 minutes with an average of 2 to 3 minutes. In a few 

 of the plants exhaust boxes have been replaced with turret steam flow 

 seamerSo Only one plant in California employs vacuum seamers but these 

 are used almost exclusively in the Pacific Northwest. On the Atlantic 

 coast all three methods were used in different plants, 



WASHING AND PROCESSING CANS 



A wide variety of can washers were employed. These were of two 

 types. In one type the cans passed through a confined space and were 

 sprayed with a hot detergent or soap solution and in the other they 

 were passed directly under a soap or detergent solution. In many 

 instances the cans passed between rotating brushes. In all cases a 

 final wash or spray vdth hot water was received. 



A considerable difference in thoroughness of washing of cans was 

 observed in the different plants. In some instances the cans were com- 

 pletely clean with no trace of oil film or oil droplets. In the worst 

 instances the cans were covered with an unsightly film of oil. Such a 

 condition will show up on the labels and, especially if a white or light 

 colored background is employed, the label will take on a dirty tan or 

 grey appearance. The difference in thoroughness of washing did not seem 

 to be correlated in any way with the tj^pe of washer used. Some of the 

 most complicated washers were observed to be doing poor jobs. It is be- 

 lieved that the efficiency of the washer is largely determined by the 

 way in v*iich it is operated. Good operation includes maintaining both 

 water tonperature and an adequate amount of soap or detergent compound 

 in the water. Some plants had ' automatic equipment to add cleaning 

 compound as needed. 



In most cases some standard detergent or alkaline soap powder such 

 as Turko, Mido, or Oakite was employed, A few plants used their own 

 specially compounded chemical mixtures. 



Processing takes place in 4 to 10 car standard horizontal retorts 

 using basket cars. Some were of the double-ended type permitting cars 

 to be rolled in one end and out the other. In California all retorts 

 racist be provided with recording charts and processing must conform to 

 cerxain standards laid down by the State Public Health Department 



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