Cable Design and Manufacture for the 

 Transatlantic Submarine Cable System 



Bv A. W. LEBERT,* H. B. FISCHER* and M. C. BISKEBORN* 



(Manuscript received September 19, 1956) 



The transatlantic cable project required that two repeatered cables be laid 

 in the deep-water crossing between Newfoundland and Scotland, and one 

 across the shallower waters of Cabot Strait. The same structure was adopted 

 for the cables laid in the two locations. 



This paper discusses the considerations leading to design of the cable and 

 describes the method of manufacture, the means and equipment for control 

 of cable quality, the process and final inspection procedures, the electrical 

 characteristics of the cable, and factors relating to mechanical and electrical 

 reliability of the final product. 



DESCRIPTION OF CABLE 



General features of the cable structure adopted for the transatlantic 

 cable project^ are illustrated in Fig. 1. The cable consists of two basic 

 parts: (1) the coaxial, or the electrical transmission path, and (2) the 

 armor or outer protection and strength members. 



The coaxial is made up of three parts: (1) the central conductor, (2) 

 the insulation, and (3) the outer or return conductor. The central con- 

 ductor is composed of a copper center wire surrounded by three helically 

 applied copper tapes. The insulation is a polyethylene compound which 

 is extruded tightly over the central conductor. The insulated central con- 

 ductor is called the cable core. The outer or return conductor is com- 

 posed of six copper tapes applied helically over the insulation. 



The protection and strength components shown in Fig. 1 for the type 

 D deep water cable are provided by a teredo tape of thin copper applied 

 over the outer coaxial conductor, a fabric tape binding, a layer of jute 

 rove for armor bedding, the textile covered armor wires and finally, 

 two layers of jute yarn flooded with an asphaltum-tar compound. This 

 cable is characterized by the extra tensile strength of its armor wires and 

 by the extra precautions taken to minimize con-osion of these wires. 



* Bell Telephone Laboratories. 



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