GB1044738A - Buoyant electric cable - Google Patents

Abstract

1,044,738. Buoyant cables. BOSTON INSULATED WIRE & CABLE CO. Oct. 7, 1964, No. 40829/64. Heading H1A. A cable is made buoyant by the provision of a number of braided openwork sleeves which provide voids to reduce the specific gravity of the cable to less than one. The cable shown comprises two different types of cores. The first has a central copper wire 14, which may be stranded, surrounded by a foamed polyethylene sheath 16 which has a specific gravity of about 0.5. Surrounding this shield is a braided silverplated copper jacket 18. This jacket is encased in flotation sleeves each made of an open construction of braided polyethylene filaments 20, 22. The second type comprises a central stranded polyethylene filament 26 surrounded by cores 24 each comprising a wire with an extruded polyethylene jacket. Over all the cores is a wrapping of aluminium-backed plastic tape 30 the metallic side facing outwardly and in contact with it an openwork metal braid 32, the two forming a screening layer. Next follow four flotation layers, each of openwork polyethylene braiding, a layer of tape of polyethylene terephthalate and a waterproof buoyant jacket 42 which is made of rubber. Layer 40 acts to separate the braiding from the rubber in case of incompatibility. The cable is completed by an armouring sheath of flat stainless steel strip and an outer flotation jacket of foamed polyethylene 46.