摘要:
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.
摘要:
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.
摘要:
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.
摘要翻译:具有导体的半导体屏蔽体和导体接触的直流电缆,由半导体屏蔽物周围的绝缘材料带形成的多层绝缘层,围绕绝缘层的另一半导体屏蔽层 以及在另外的半导电屏蔽周围的金属护套,绝缘层浸渍有非迁移性绝缘组合物,其滴点温度高于电缆的最大工作温度至少5℃并具有电负性气体 溶解在其中,在低于组合物的滴点温度的温度下,气体在组合物中的扩散系数在3×10 -5至3×10 -6 cm 2 / sec的范围内。
摘要:
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.
摘要:
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. A further layer of plastic material may be interposed between the metal sheath and the plastic material layer of the core and may at least partially extend into the grooves.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.