156 SCIENCE OF SUCCESSFUL THRESHING 



of times belt should go around in a minute. For example : 

 If cylinder be a 2O-bar, its speed should be 750 and the 

 regular pulley 5294^ for this is 13^/2 inches in diameter or 

 42 inches in circumference. Multiplying 750 by 42 gives 

 31,500 inches as the product. Dividing this by 12 to re- 

 duce to feet gives 2625 feet per minute as the required 

 travel of the belt. If this be 120 feet long, dividing by 120 

 gives 22 (nearly) as the required number of rounds of the 

 belt per minute. With a 150 foot belt, the number of 

 rounds will be nearly 18 or with 160 foot belt 17 (nearly) 

 rounds. In the same manner, the required number of 

 rounds can be figured for any cylinder speed, cylinder pul- 

 ley or length of belt. 



Cylinder Boxes. The cylinder boxes are the most im- 

 portant bearings on a separator and they must receive a 

 certain amount of attention or there will be trouble. All 

 Case cylinders are fitted with ball and socket self-aligning 

 boxes, which practically eliminate all possibility of their 

 heating from improper alignment. The boxes on 2O-bar 

 cylinders are about eight inches long, allowing a good bear- 

 ing surface for these large cylinders and all are fitted with 

 oil cups which hold a sufficient quantity of oil to amply 

 lubricate the bearings. The chapter on "Lubrication and 

 Hot Boxes" should be read with special reference to the 

 cylinder boxes. 



To Take "End Play" Out of the Cylinder. Loosen 

 lower half of housing of box by slacking the nuts which 



