The present disclosure relates to a power cable and an intermediate connection structure, for connection thereof, which is capable of preventing the concentration of stress on a soldered part, which is configured to join a metal sheath of the power cable and a metal sheath restoration layer of the intermediate connection structure while ensuring airtight or watertight sealing therebetween, preventing deformation of or damage to the soldered part due to stress applied thereto, and minimizing thermal history in the power cable during the formation of the soldered part.

An alternating current (AC) power cable includes a conductor surrounded by at least an inner semiconductive layer including a first semiconductive composition, an insulation layer including a polymer composition, an outer semiconductive layer including a second semiconductive composition, and optionally a jacketing layer including a jacketing composition, in that order. The polymer composition of the insulation layer includes an unsaturated low density polyethylene (LDPE) copolymer of ethylene with one or more polyunsaturated comonomers and a crosslinking agent. The polymer composition of the insulation layer has a dielectric loss expressed as tan (50 Hz) of 12.010.sup.4 or less, when measured at 25 kV/mm and 130 C. according to Test for Tan measurements on 10 kV cables.

Provided is a power cable, particularly, an ultra-high voltage underground or submarine cable for long-distance direct-current transmission. More specifically, the present invention relates to a power cable, in which an insulating layer has high dielectric strength, an electric field applied to the insulating layer is effectively reduced, and particularly, a void is suppressed from occurring in the insulating layer due to contraction of insulating oil, caused by a decrease of temperature in the insulating layer under a low-temperature condition or when the supply of an electric current is stopped, thereby effectively suppressing partial discharge, dielectric breakdown, etc. due to an electric field concentrated in the void.

High voltage three-phase cable comprising three cores positioned so as to assume the configuration with minimum radial dimension and a sheath surrounding the three cores, wherein each core comprises an electric conductor having a substantially triangular shaped cross section with vertex portions and edges; an insulating system surrounding the electric conductor, the insulating system comprising an inner semiconducting layer surrounding the electric conductor, an insulating layer surrounding and in contact with the inner semiconducting layer and an outer semiconducting layer surrounding and in contact with the insulating layer, the layers of the insulating system being made of an extruded polymeric material having a dielectric constant comprised from 2 to 2.5; and a metallic screen surrounding the insulating system.

A cable including a conductor. An insulation system surrounds the conductor. A metallic screen surrounds the insulation system. A jacket surrounds the insulation system. The metallic screen is constructed of stainless steel.

Provided is a power cable, particularly, an ultra-high voltage underground or submarine cable for long-distance direct-current transmission. More specifically, the present invention relates to a power cable, in which an insulating layer has high dielectric strength, an electric field applied to the insulating layer is effectively reduced, and particularly, a large void is suppressed from occurring in the insulating layer when the power cable is left at low temperatures for a long time until electric current is supplied thereto after installed in a low-temperature environment, thereby effectively preventing partial discharge, dielectric breakdown, etc. from occurring due to an electric field concentrated in the large void.

A cable includes a conductor and a first semiconductive layer arranged in a radially outer position with respect to the conductor. An insulating layer is arranged in a radially outer position with respect to the first semiconductive layer. A second semiconductive layer is arranged in a radially outer position with respect to the insulating. A conductive screen is arranged in a radially outer position with respect to the second semiconductive layer. A heat block layer is arranged in a radially outer position with respect to the conductive screen. The heat block layer includes a layer made of a fire resistant or a flame retardant halogen-free material. A rubberized glass fiber tape is arranged in a radially outer position with respect to the heat block layer. An outer sheath is arranged in a radially outer position with respect to the rubberized glass fiber tape.

A method of building an insulation system around an axial section of a conductor of a power cable, the method including: a) providing a power cable including a conductor and an insulation system arranged around the conductor, the insulation system including insulation system layers, including an inner semiconducting layer arranged around the conductor, an insulation layer arranged around the inner semiconducting layer, and an outer semiconducting layer arranged around the insulation layer, wherein the power cable includes an axial section between a first insulation system section and a second insulation system section of the insulation system which at least is without an outer semiconducting layer, b) winding a tape around the conductor along the axial section in a plurality of layers to form a plurality of layers of tape connecting with the first insulation system section and the second insulation system section, and c) heating the plurality of layers of tape to melt and fuse the plurality of layers of tape to form an insulation system layer between the first insulation system section and the second insulation system section, wherein the tape has a width defined by a distance between lateral edges, wherein the tape has a mid-section between its lateral edges, wherein in the mid-section the tape has a largest thickness, and wherein the thickness of the tape decreases from the mid-section towards both lateral edges.

An insulated electrically conductive element (1) for the aerospace field, has an elongate electrically conductive element surrounded by at least two layers. The two layers are being an electrically insulating layer (4) surrounding the elongate electrically conductive element (2) and a first semiconductor layer (5) surrounding the electrically insulating layer (4). At least one of the layers has having at least one fluoropolymer.

Provided is an insulating resin composition for a DC power cable, which insulating resin composition has excellent extrudability, is unlikely to experience sagging, has good scorch resistance, generates a smaller amount of secondary decomposition water, can form an insulating layer that stably exhibits good DC electrical properties, and has high extrusion stability. The insulating resin composition for a DC power cable according to the present invention includes (A) a low-density polyethylene having a complex viscosity *.sub.100, which is measured at 130 C. and a frequency of 100 rad/s, of 600 to 1,300 Pa.Math.s, wherein a ratio (*.sub.0.1/*.sub.100) of a complex viscosity *.sub.0.1, which is measured at 130 C. and a frequency of 0.1 rad/s, to the complex viscosity *.sub.100 is 4 or more; (B) a modified polyethylene; and (C) a stabilizer including a mixture of a hindered phenol antioxidant and a thioether antioxidant. The amount of carbonyl groups introduced into the resin composition through the component (B) is 710.sup.6 to 1.310.sup.5 mol/g relative to the total mass of the component (A), the component (B), and the component (C).