STATE OF THE ART OF ELECTRO-MECHANICAL CABLES 



Technical Note N-1303 



3.1340-1 



by 



J. R. Padilla, M. C. Hironaka, R. D. Hitchcock, J. F. Jenkins, C. L. Liu, 

 R. J. Malloy, J. F. McCartney, T. Roe, Jr., and K. D. Vaudrey 



ABSTRACT 



A state-of-the-art study was made of submarine electro-mechanical 

 cable technology. These are ocean cables which include electrical cables 

 with special strain members. The purpose of the study was to define 

 areas of deficiencies so that development programs could be initiated in 

 selected areas. 



The approach included a literature search, and extensive interviews 

 with electro-mechanical cable manufacturers and electro-mechanical cable 

 users. Engineers and scientists of various disciplines from the Naval 

 Civil Engineering Laboratory participated in the study. Areas of study 

 include: 



Mechanical Properties 



Electrical Properties 



Handling 



Terminations and Hardware 



Maintenance and Repair 



Manufacturing 



History of Electro-Mechanical Cable Development 



The technological development of submarine electro-mechanical cables 

 dates from the mid-nineteenth century with their use as telegraph and, 

 later, telephone cables. There is, therefore, a voluminous literature on 

 ocean bottom communication cables. The wide use of electro-mechanical 

 cables suspended above the seafloor began within the past twelve years. 

 These cables include electro-mechanical cables deployed above the sea- 

 floor and can, with few exceptions, be included in two categories: struc- 

 tural cables, used as tensile members in support of structures tethered 

 to the seafloor; and working cables, typically deployed and retrieved by 

 winch into the sea from a surface or subsurface platform. A special case 

 of working electro-mechanical cables, oil well logging cables, have 

 technological developments dating back to the 1930's. 



Electro-mechanical cable technology has benefited from communications 

 and well logging technology, but deficiencies are still present. These 

 deficiencies can be generally categorized in the four areas of: design 

 of electro-mechanical cables and terminations; specifications and testing; 

 handling; and repair and maintenance. 



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