. The Bell System technical journal . e cable, more than half of the total time is taken up in filling the cylinder with lead and cooling it under pressure to a point where it can be extruded. The tendency, therefore, has been to build presses with larger lead containers, and in turn of larger capacity, s Page 134, \ol. 2, Industrial and Engineering Chemistry, April 15, 1930—articleby A. C. Walker and E. J. Ernst, Jr. 454 BELL SYSTEM TECHNICAL JOURNAL in order to make the productive time of extrusion a larger percentage ofthe complete cycle of operation. Until recently presses were usedhaving
. The Bell System technical journal . e cable, more than half of the total time is taken up in filling the cylinder with lead and cooling it under pressure to a point where it can be extruded. The tendency, therefore, has been to build presses with larger lead containers, and in turn of larger capacity, s Page 134, \ol. 2, Industrial and Engineering Chemistry, April 15, 1930—articleby A. C. Walker and E. J. Ernst, Jr. 454 BELL SYSTEM TECHNICAL JOURNAL in order to make the productive time of extrusion a larger percentage ofthe complete cycle of operation. Until recently presses were usedhaving a 30 in. diameter ram and a 42 in. stroke. Such a press has acapacity of 1100 lbs. of lead per charge and extrudes a maximum of4500 lbs. per hour. This type of press has the water ram locatedbelow the floor line. The die block and lead cylinder therefore riseslowly as the lead is forced out around the cable core. This varyingheight of the cable as it is extruded in relation to the floor introducedsome difiiculties in the Fig. 22—34-in. inverted press. The latest type of press used at Baltimore is illustrated by Fig. 22and is known as the 34 in. inverted press. It was designed andbuilt by one of our outstanding American engineering firms. Itsstroke is 56 in.; the diameter of the ram is 10| in., with a lead capacityof 1800 lb. per charge and a maximum extrusion rate of 5680 lb. perhour. This press is approximately 21 ft. in height above the floor line,and has the water cylinder mounted between the four columns at thetop of the press. The 34 in. diameter water ram has the steel lead rambolted to it. Connection is made from the water cylinder to a hy-draulic pump, Fig. 23, supplying water at a maximum pressure of LEAD-COVERED PAPER-INSULATED TELEPHONE CABLE 455 5500 lb. per sq. in. The four steel columns supporting these topcastings are 12^ in. in diameter. The steel ram during extrusiona pressure of approximately 59,000 lb. per scj. in. on the lead. At thef
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
