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BELL SYSTEM TECHNICAL JOURNAL 



in order to make the productive time of extrusion a larger percentage of 

 the complete cycle of operation. Until recently presses were used 

 having a 30 in. diameter ram and a 42 in. stroke. Such a press has a 

 capacity of 1100 lbs. of lead per charge and extrudes a maximum of 

 4500 lbs. per hour. This type of press has the water ram located 

 below the floor line. The die block and lead cylinder therefore rise 

 slowly as the lead is forced out around the cable core. This varying 

 height of the cable as it is extruded in relation to the floor introduced 

 some difiiculties in the operation. 



Fig. 22 — 34-in. inverted press. 



The latest type of press used at Baltimore is illustrated by Fig. 22 

 and is known as the 34 in. inverted press. It was designed and 

 built by one of our outstanding American engineering firms. Its 

 stroke is 56 in.; the diameter of the ram is 10| in., with a lead capacity 

 of 1800 lb. per charge and a maximum extrusion rate of 5680 lb. per 

 hour. This press is approximately 21 ft. in height above the floor line, 

 and has the water cylinder mounted between the four columns at the 

 top of the press. The 34 in. diameter water ram has the steel lead ram 

 bolted to it. Connection is made from the water cylinder to a hy- 

 draulic pump, Fig. 23, supplying water at a maximum pressure of 



