1102 THE BELL SYSTEM TECHNICAL JOURNAL, SEPTEMBER 1953 

 BASIC PROCESS 



The starting point in the process is commercial improved plow steel 

 wire 0.0336" in diameter delivered on 450-pound reels. Twenty-five 

 strands pass through the plating machine in parallel at 100 feet per 

 minute: After suitable cleaning, approximately 2-3/^ thousandths of copper 

 plus a thin plate of lead and brass are electrolytically deposited on the 

 wire. To apply this deposit requires nine different electrolytes, approxi- 

 mately 80,000 amperes at 5 volts, and a 600-ft machine with a wire span 

 from supply to take-up of 850 feet. 



The plating portion of the machine is a relatively simple structure 

 consisting of a long trough containing plating cells alternating with con- 

 tact rolls. The electrolytes are pumped into the plating cells through 

 which the wire passes, cascade into return troughs, flow back to reser- 

 voirs and are continuously recirculated. The contact rolls position and 

 propel the wires through the machine and serve as the means of makin§ 

 electrical contact. 



The general structure of the machine is uniform throughout, only the 

 material changing to fit the chemical requirements of the electrolyte in 

 the particular section. The wire, in passing from one electrolyte to an- 

 other, travels through washing and wiping facilities mounted in the 

 troughs to prevent contamination of electrolytes and reduce dragout of 

 valuable solutions. The finished wire, controlled to specified conductiv- 

 ity, is then taken up on reels ready for insulating. 



THE BUILDING 



The building is 91 feet wide by 340 feet long, of brick and steel con- 

 struction, in keeping with Point Breeze architecture. It was specifically 

 designed to fit the process. The first floor is given over to wire supply 

 and take-up, electrolyte mixing, pumping and conditioning and material 

 storage. All plating operations take place on a mezzanine. The upper 

 portion of the building is divided into three bays by a pair of lengthwise 

 partitions. The center section contains the two plating machines, each 

 machine being constructed in the form of the letter ''C", the two ''C" 

 shaped machines being placed face to face. The outer bays contain the 

 rectifiers, electrical controls and heating and ventilating equipment. The 

 floor of these bays is steel grating. The partitions prevent the entrance 

 of any vapors released by the heated plating solutions, and the ventilat- 

 ing equipment forces a steady stream of clean and tempered air down- 

 ward over the electrical facilities and through the grating into the first 

 floor area below. 



The ventilating equipment draws in fresh air from the roof, heats it 



