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MARINE PRODUCTS OF COMMERCE 



as 360 collapsed cans can be placed in a case holding only 48 ordinary cans. The 

 tops and bottoms are packed separately. Before the collapsed cans are used they 

 are run through a machine which expands them and puts on the bottom, thus sav- 

 ing considerable shipping and storing space. 



The empty cans are usually stored on the second story of a cannery and fed 

 down a chute into the automatic filling machine, which fills each can with the 

 proper amount of fish and adds the desired amount of salt. A recent type of filling 

 machine cuts the fish into slices, salts the cans, and fills them at the rate of 115 



(.Courtesy U. S. Fish and Wildlife Sen'icc) 



Fig. 20-5. The vacuum can sealing machine requires adjustment 

 from time to time. Many canneries make use of this method for sealing 

 cans. 



to 125 per minute. Many of the flat cans are filled by hand; this is particularly 

 true when they are to hold chinook and sockeye salmon. The filled cans are then 

 carried on belts to the "patching table," where they are either weighed auto- 

 matically and inspected to see that they contain the proper amount of fish and have 

 no bones or skin showing at the top. From the "patching table" they pass on mov- 

 ing belts to the "clincher" machine, where tops are loosely crimped on to prevent 

 particles of fish from getting out of and condensation water from getting into 

 the cans during their passage through live steam in the "exhaust box." 



The function of the "exhaust box" is primarily to heat the filled cans sufficiently 

 to drive out some of the air; it is necessary to have a vacuum in the cans after 



