Abstract: A submarine, optical fiber telecommunication line having optical fiber cables with external armor interconnected with optical fiber cables with only internal armor by opto-electronic repeaters and tubular bodies. The repeaters, the tubular bodies and the cables can withstand the tensile and hydrostatic stresses to which they are subjected during laying and after laying. At the shore ends, the repeaters are mechanically connected at one of their ends to cables with external armor. The other ends of the repeaters are mechanically connected to the tubular bodies which are mechanically connected to the sheaths and the internal armor of cables with only internal armor. The tubular body has an internal partition to which the internal armor is mechanically connected and has an internal sealing plug for preventing axial flow of water.

Abstract: A joint between two different types of optical fiber cables, the tension and compression stresses to which the cables are subjected being withstood in one of the cables by a centrally disposed armor having the optical fibers therearound and in the other of the cables by an armor surrounding the optical fibers. The joint includes a plate with a central opening, a plurality of spaced second openings around and spaced from the central opening and a plurality of spaced third openings around and spaced from the second openings, the central armor being secured in the central opening, the armor of the other cable being secured in the third openings and the optical fibers of one of the cables extending through the second openings and being connected to the optical fibers of the other cable. A protective body extends from one cable to the other and encloses the plate, the securing devices, the connections and the portions of the armors and the fibers intermediate the cables.

Abstract: An optical fiber submarine cable having only a central rope for withstanding the stresses to which the cable is subjected, a plastic core with interrupted but closed or substantially closed, grooves at its outer portion, at least one optical fiber in each groove, a sheath around the core, and a substantially incompressible fluid filling all otherwise empty spaces within the sheath including any such spaces between the wires of the rope and in the grooves. The grooves are separated by ribs, and before the sheath is applied the diameter of the core at the ribs is greater than the diameter of the inner surface of the sheath and the sides of the ribs are separated to provide grooves opening outwardly of the core. Also, a process for manufacturing such a cable.

Abstract: A direct current electric cable with a conductor, a semi-conductive screen around and contacting the conductor, a plurality of layers of insulation formed by tapes of insulating material around the semi-conductive screen, a further semi-conductive screen around the layers of insulation and a metal sheath around the further semi-conductive screen, the layers of insulation being impregnated with a non-migrating, insulation composition having a dropping point temperature at least 5.degree. C. above the maximum operating temperature of the cable and having an electronegative gas dissolved therein, the gas having a coefficient of diffusion in the composition in the range from 3.times.10.sup.-5 to 3.times.10.sup.-6 cm.sup.2 /sec at temperatures below the dropping point temperature of the composition.

Abstract: A hollow cylindrical, watertight casing housing optoelectronic repeater components, having optical fibers extending therefrom, and having a bore in which a tension resisting rope is received and is insulated from the wall of the bore. The casing is enclosed by a water-tight, tubular box which has a pair of cylindrical bodies extending therefrom, one at each end of the box. Each cylindrical body has a centrally disposed length of rope surrounded by polymeric material in which optical fibers are embedded, and the polymeric material is surrounded by a metallic sheath. The optical fibers of the cylindrical bodies are connected within the box to the optical fibers extending from the casing. The lengths of rope of the bodies are mechanically connected at one end respectively to opposite ends of the rope in the bore and at the opposite end respectively to ropes of submarine optical fiber cables having similar ropes, optical fibers and a metallic sheath.

Abstract: Process and apparatus for making a cable with filiform elements, such as protected optical fibers or electrical conductors, in open-helix configuration and embedded in a polymeric material. The elements are fed through an extruder where the polymeric material in a plastic state is extruded thereover. The polymeric material with the elements therein is twisted in alternate directions around the cable axis as such material is advanced. The polymeric material is cooled downstream of the extruder to fix the elements in open-helix configuration. The polymeric material may be so twisted by alternately rotating a portion of the extruder in contact with the polymeric material in opposite directions or if the cable includes a central rope, by so twisting the rope in advance of the extruder with a pulley engaging the rope and rotated in a direction transverse to the plane of rotation of the pulley and around the axis of the rope.

Abstract: A submarine cable with optical fibers which prevents damage to the fibers due to water pressure without the use of an external armor. The cable has a central core with a strand which provides the cable tensile strength and which is surrounded and contacted by a layer of plastic material which has helical grooves which receive the optical fibers which may have a protective covering. The layer of plastic material is surrounded by sheath in the form of a layer of plastic material. The grooves and any spaces radially inwardly of the sheath, such as the spaces between the wires of the strands, are filled with a substantially incompressible fluid, such as a grease or jelly. If the optical fiber protective layer is a tube loosely receiving the optical fiber, or optical fibers, the space within the tube not filled by optical fibers is filled with a substantially incompressible fluid. The layer of plastic material forming the sheath may at least partially extend into the grooves.

Abstract: A joint for interconnecting a pair of optical fiber, submarine cables which have a central armor sufficient to withstand tensile stresses applied to the cables during use, i.e., laying, recovery and operation, which have optical fibers loosely disposed in channels in a plastic layer around the central armor and which have all otherwise empty spaces filled with a substantially incompressible fluid. The joint comprises a metal ferrule or a weld mechanically interconnecting the ends of the armors of the cables. A plastic joint sheath surrounds the interconnection of the armors and has channels which interconnect the respective channels of the cables. The optical fibers are loosely received in and interconnected within the joint sheath channels. Any otherwise empty spaces within the plastic joint sheath are filled with a substantially incompressible fluid.

Abstract: A submarine cable with optical fibers which prevents damage to the fibers due to tensile stresses or water pressure without the use of an external armor. The cable has a central core with an anti-torsional wire rope around which a plurality of tubes are helically wound. Each tube loosely contains at least one optical fiber, and the spaces within the tubes and any spaces within the rope are filled with a substantially incompressible fluid. The core is surrounded by a sheath of plastic material which contacts the tubes and the rope in a manner which eliminates voids between the sheath and the core elements. The rope may have a cladding of plastic material, and the rope may have a wire or tape of good conductivity metal for supplying electrical power to repeaters.

Abstract: A joint between a pair of optical fiber submarine cables having a central armoring in the form of a wire rope, optical fibers disposed around the armoring and a sheath around the optical fibers. The joint contains a watertight housing for optoelectronic repeaters which has a central through-cavity into which the end portions of the armoring, or an interconnecting armoring, extend, and the end portions are mechanically secured together within the through-cavity, or to the ends of the interconnecting armoring which are outside the housing. The sheaths are interconnected by a metallic casing surrounding and secured to the housing for the repeaters, and the sheaths may also be connected to the housing by further metal casings. The housing for the repeaters is secured to the armorings of the cables or the interconnecting armoring.

Abstract: An oil-filled electric cable in which the solid insulation is formed, at least in part, by separately applied, alternate layers of cellulose paper tape and of film tapes made of a plastic. Prior to application of the tapes around the cable conductor, the moisture content of the paper tape is selected and the swelling of the plastic tape by the oil after application is adjusted, if necessary, such as by immersing the plastic tape in the oil prior to application, so that the swelling of the plastic tape by the oil in the formed cable is offset by the shrinkage of the paper tape during drying of the cable. Also, apparatus for pre-swelling the plastic tape.

Abstract: Joints for optical fiber, submarine cables in which the tensile resistant element is centrally located in the cables, rather than at the exterior of the cables, and all spaces between the cable elements are filled with a substantially incompressible fluid. In the joint, the end of the tensile resistant element of one cable is joined to the end of the tensile resistant element of the other cable by a tubular clamp which is surrounded by a plastic layer having through-cavities in which the optical fibers are received and joined. If the optical fibers are in fluid filled tubes, the tubes are connected by further fluid-filled tubes surrounding the optical fiber connections. The plastic layer may be surrounded by a further plastic layer, and the cable metal sheaths are interconnected by a metal tube in watertight relation to the sheaths.

Abstract: A submarine cable with optical fibers which prevents damage to the fibers without the use of an external armor. The cable has a central strand which provides the cable tensile strength and which is surrounded by helically wound and circumferentially spaced tubes which loosely enclose the optical fibers. Helically wound electrical conductors are intermediate and contact the tubes. A layer of plastic material surrounds the tubes and the electrical conductors. The tubes, any spaces in the strand and any spaces radially inwardly of the layer of plastic material are filled with a substantially incompressible fluid, such as a grease or jelly.

Abstract: A submarine cable with optical fibers which prevents damage to the fibers due to water pressure without the use of an external armor. The cable has a central core with a strand which provides the cable tensile strength and which is surrounded and contacted by a layer of plastic material having helical grooves which receive the optical fibers which may have a protective covering. The layer of plastic material is surrounded by a thin metal sheath which, in turn, is closely surrounded by a layer of plastic material. The grooves and any spaces radially inwardly of the sheath, such as the spaces between the wires of the strands, are filled with a practically incompressible fluid, such as a grease or jelly. If the optical fiber protective layer is a tube loosely receiving the optical fiber, or optical fibers, the space within the tube not filled by optical fibers is filled with a substantially incompressible fluid.

Abstract: A submarine cable with optical fibers which prevents damage to the fibers due to water pressure without the use of an external armor. The cable has a central strand which provides the cable tensile strength and which is surrounded by helically wound tubes which enclose the optical fibers. A layer of plastic material may be provided intermediate the tubes and the strand and the tubes are covered by a layer of plastic material in contact with the tubes. The layer of plastic material contacting the tubes is closely surrounded by a thin metal sheath which, in turn, is closely surrounded by a layer of plastic material. The tube and any spaces radially inwardly of the tubes are filled with a practically incompressible fluid, such as a grease or jelly. The strand may include a wire of good electrical conductivity which, with the sheath, may be used to supply electrical power to repeaters along the cable length.

Abstract: An oil-filled electric cable in which the solid insulation is formed, at least in part, by separately applied, alternate layers of cellulose paper tape and of film tapes made of a plastic. Prior to application of the tapes around the cable conductor, the moisture content of the paper tape is selected and the swelling of the plastic tape by the oil after application is adjusted, if necessary, such as by immersing the plastic tape in the oil prior to application, so that the swelling of the plastic tape by the oil in the formed cable is offset by the shrinkage of the paper tape during drying of the cable. Also, apparatus for pre-swelling the plastic tape.

Abstract: Method for improving the dielectric strength of insulation not subject to fluid pressure and used to insulate a conductor element, such as the conductor of a cable, an insulator, etc., subjected to direct current high voltage in which, during or prior to service use thereof, the insulation is subjected continuously or intermittently to a varying amplitude, direct current voltage. The amplitude of the variation is small relative to the average value of the direct current voltage and the frequency of the variation, preferably, is less than 60 Hz. Also, apparatus for providing the voltage of varying amplitude including an alternating current generator in series between the direct current source and the conductor element and inductor in parallel with the generator, the inductor having a low ohmic resistance and a high reactance relating, respectively, to the ohmic resistance and reactance of the generator.

Abstract: A submarine electric cable installation in which the cable is protected from damaging stresses to which it would be subjected if it were permitted to be suspended between projections on the water bottom by enclosing the portion of the cable which would normally engage the projections with a tubular stiffening means, the stiffening means having a rigidity greater than the rigidity of the cable and providing a space between it and the cable for cooling water flow. The stiffening means may comprise one or more tube and, preferably, comprises a plurality of tubes having their ends secured to the adjacent ends of other tubes, each tube comprising a pair of C-shaped shells with annular corrugations and secured together. Also, a method of applying the tubes to the cable in which the tubes are applied to the cable, as it is laid, between the laying ship and the surface of the water.

Abstract: The invention concerns an improvement in taped cables having large diameter and suitable for use at voltages up to and over 1000 kV. The taping of one or more layers is wound according to a double-start or multi-start helix, said helix having an inclination less than 75.degree..

Abstract: Methods and apparatus for forming a cable element comprising a core of plastic material with helical surface grooves containing one or more optical fibers. The core has one or more reinforcing elements resistant to tension and compression and is covered with a covering of tape or thermoplastic. The core is fed to a rigid body having tongues corresponding to and entering into the grooves, and the optical fiber or fibers are fed into the grooves through through-holes in the body which extend from the exterior surface of the body to the tongues and which are inclined with respect to the axis of the core. The core feeding means may be a pay-off bobbin or a core extruder with a threading die, and by increasing the feed rate of the fibers relative to the feed rate of the core or by stretching the core in advance of the rigid body, the lengths of the fibers in the grooves may be longer than the lengths of the grooves.