Abstract: In an optical fibre submarine cable the ingress of hydrogen ions is reduced if not eliminated by at least one envelope which provides a barrier to hydrogen ions.In one embodiment a copper tape (L) is folded longitudinally around the cable core comprising strength member wires (G,H) split aluminium or coppr tube (E) and optical fibre package (A). The abutting edges (L') are seam welded with less than 0.1% skips. Preferably the folded copper tape is longitudinally welded while a loose fit and subsequently reduced in diameter to leave an accurately determined small annular gap between tubes E and F which is filled with a water blocking material that is highly viscose at ambient temperature and effectively glues the tubes together.

Abstract: At least one metallic element is incorporated into a cable during the manufacture of optical fiber cables, along with one or more elongated optical fibers. Such metallic element with its insulation is similar in diameter to an optical fiber with its sheath. The electrical resistance of the metallic element varies very little with temperature, but does vary with strain. Hence, by monitoring the resistance of the metallic element, the strain to which the fibers are subjected can also be monitored.

Abstract: An optical fiber submarine cable is made by extruding a metallic pressure tube by a friction extrusion technique, compressing the tube, applying tensile strength members, applying a conductive tape over the strength members and extruding plastic dielectric material over the tape. Armoring can subsequently be applied for shallow water application.

Abstract: An optical fibre submarine cable is made by extruding a metallic pressure tube by a friction extrusion technique, compressing the tube, applying tensile strength members, applying a conductive tape over the strength members and extruding plastic dielectric material over the tape. Armoring can subsequently be applied for shallow water application.

Abstract: An optical fiber cable intended for submarine use has a central cylindrical strength member (1) over which are laid the optical fibers (2). These are within a sheath 3, itself within an aluminum tube (4), usable to convey electrical power for repeaters. On the outside of this tube we have a layer of high tensile steel wires (5), surrounded by a layer of low density polyethylene.In a cable for shallower waters where the risk of damage is greater than in deep water the polyethylene layer is surrounded by a layer of armouring wires separated from the polyethylene by bedding material and enclosed by a layer of binding material.

Abstract: A major problem in the manufacture of optical fibre cables is the strain to which the fibres are subjected, which strain could damage the fibres. To enable this strain to be monitored, and hence remedial action to be taken, one or more metallic elements are incorporated in the cable, each such element with its insulation being similar in thickness to an optical fibre with its sheath. The electrical resistance of the metallic elements varies very little with temperature, but does vary with strain, so by monitoring resistance, one monitors strain.Although mainly intended for use during manufacture, the method can be used whenever strain monitoring is needed.

Abstract: A high pressure gland for optical fibres and/or electrical conductors has a tubular member through which the fibres/conductors are loosely passed. The bore of the tube is then filled with an encapsulating plastics material which adheres to both the fibres/conductors and the wall of the tube bore. The outside of the tubular member is shaped so as to be mechanically secured and sealed in an aperture in a bulkhead or the like. The construction of the gland is such that it can withstand a high axial pressure differential such as might be experienced on the sea bed.

Abstract: An optical fiber cable, particularly for submarine cable use, has its fibers enclosed within a tubular electrical conductor which is itself overlayed by a dielectric layer. This layer is itself overlayed by a strength member formed of closely adjacent wires.