APPLICATION OF REFRIGERATION TO HANDLING OF MILK. 35 



scale. In double-pipe condensers and coolers it is not such an easy- 

 matter to clean them as 

 it is necessary to take 

 off a return bend from 

 the end of the condenser 

 or cooler in order to ex- 

 amine or clean them. 

 This should be done 

 frequently, and if the 

 inner pipe is found to 

 be coated with a soft 

 substance it can be re- 

 moved by the aid of an 

 or din ary flu e brush . If , 

 however, the coating is 

 in the form of scale, it 

 will be necessary to bore 

 it out on a lathe or tube- 

 boring machine. 



The life and satisfac- 

 tory operation of all me- 

 chanical apparatus are 

 dependent on proper 

 care as well as on the 

 original design. It is 

 therefore necessary that 

 such apparatus should 

 receive frequent and 

 careful inspection and 

 prompt correction of all 

 defects found. As clean- 

 liness is essential for the 

 satisfactory operation of 

 machinery of all kinds, 

 the wearing parts of the 

 machine should be kept 

 free from dirt and grit 

 and the oilways open, 

 well lubricated, and ad- 

 justed. The clearance 

 of the pistons should be 

 adjusted to a minimum, 

 both in the steam and 

 compressor cylinders. 



In operating an ammonia plant the gages should be carefully 

 watched, as they are the indicators of the work being done. The 



