Abstract: An electrical power transmission line includes: at least one electrical cable; a raceway made of ferromagnetic material including a base and a cover defining an inner housing space for housing the electrical cable; a wet basic filling material having a pH between 11 and 13 housed in the inner housing space and embedding the at least one electrical cable. In order to achieve corrosion protection of the raceway, the inner surface of the cover is in contact with a basic passivating material having a pH between 11 and 13.

Abstract: A magnetically shielded cable arrangement, comprising at least two AC cables (201-203) comprising a spaced portion extending between two close portions of parallel cables, such spaced portion sequentially including a diverging portion, a widely spaced portion and a converging portion, and an EMF shielding system (1) laid over said at least two AC cables (201-203), said EMF shielding system (1) comprising a conductor (2, 3, 11, 12) having two branches (2, 3) forming a median portion (4, 5) and end portions (7-10), the median portion width being equal to or larger than the AC cables distance in the widely spaced portion and the width at the extremities of the end portions (7-10) being larger than the AC cables distance in the close portions and smaller than the AC cables distance in the widely spaced portion, said conductor (2, 3, 11, 12) comprising an inner electrical path (2a, 3a) and an outer electrical path (2e, 3e) connected together (11, 12) at relevant longitudinal ends.

Abstract: A method for shielding the magnetic field generated by an electrical power transmission line and an electrical power transmission line so shielded. The electrical power transmission line has at least one electrical cable and at least one shielding element made of ferromagnetic material arranged in a radially outer position with respect to the at least one cable which shielding element has a base and a cover. The line also has a supporting element coupled to at least the base of the shielding element. In particular, the ferromagnetic material of the shielding element is selected from grain oriented silicon steel, preferably containing a silicon content between about 1% and about 5%, non-grain oriented silicon steel, Permalloyè and Supermalloyè.

Abstract: An electrical power transmission line having at least one electrical cable, a conduit of ferromagnetic material enclosing the electrical cable and having a base and a cover and electrical contact elements for electrically connecting the base and the cover, wherein the electrical contact elements are metal fusion joints or metal resilient members suitable to pierce the ferromagnetic material.

Abstract: A method for shielding the magnetic field generated by an electrical power transmission line having at least one electrical cable. A magnetic shield is provided in a position radially external to at least one electrical cable. The magnetic shield has at least one pair of shielding layers made from different ferromagnetic materials, radially superimposed and having their maximum relative magnetic permeability increasing in a radial direction from the inside toward the outside of the magnetic shield. An electrical power transmission line provided with multiple-layer magnetic shield and a multiple-layer magnetic shield.

Abstract: A process for manufacturing an electric cable. In particular, the process includes the steps of: a) feeding a conductor at a predetermined feeding speed; b) extruding a thermoplastic insulating layer in a radially outer position with respect to the conductor; c) cooling the extruded insulating layer at a temperature not higher than 70° C.; and d) forming a circumferentially closed metallic screen around the extruded insulating layer. The process is carried out continuously, i.e., the time occurring between the end of the cooling step and the beginning of the screen forming step is inversely proportional to the feeding speed of the conductor.

Abstract: A method for shielding the magnetic field generated by an electrical power transmission line having at least one electrical cable. A magnetic shield is provided in a position radially external to at least one electrical cable. The magnetic shield has at least one pair of shielding layers made from different ferromagnetic materials, radially superimposed and having their maximum relative magnetic permeability increasing in a radial direction from the inside toward the outside of the magnetic shield. An electrical power transmission line provided with multiple-layer magnetic shield and a multiple-layer magnetic shield.

Abstract: An electrical power transmission line having at least one electrical cable, a conduit of ferromagnetic material enclosing the electrical cable and having a base and a cover and electrical contact elements for electrically connecting the base and the cover, wherein the electrical contact elements are metal fusion joints or metal resilient members suitable to pierce the ferromagnetic material, so that an electromagnetic continuity between base and cover can be provided for improving the magnetic shielding properties of the conduit.

Abstract: A method for screening the magnetic field generated by an electrical power transmission line having at least one electrical cable. The cables may be inserted into a conduit having at least one layer of non-grain-oriented ferromagnetic material, having a magnetic curve with a maximum value of relative magnetic permeability (&mgr;max).

Abstract: A system for carrying electrical energy in connections in underground cables. In particular, it relates to a method of laying cables and a trench filler having a low thermal resistivity, used for laying underground cables for carrying electrical energy. More particularly, it relates to the use of an inert filler to be disposed in an area around the cables or the parts of the system, such as joints, which are disposed underground. The method of laying cables disposed in a trench includes: removing the original soil to prepare the trench; disposing a first layer of a first composition in the trench; disposing the cables on top of the first layer; disposing a second layer of the first composition on top of the cables; disposing a third layer on top of the second layer formed by a second composition to fill the trench. The first composition comprises: 60-90% by weight of crushed sand; 4-15% by weight of silt; 2-12% by weight of cement; and 4-15% by weight of water.

Abstract: A description is given of a method for screening the magnetic field generated by an electrical power transmission line comprising at least one electrical cable. The method comprises the insertion of the cables into a conduit comprising at least one layer of a non-grain-oriented ferromagnetic material, having a magnetic curve with a maximum value of relative magnetic permeability (&mgr;max) corresponding to a magnetic field value (H&mgr;max) of less than 1000 A/m. In one example, the ferromagnetic material is a steel with a low content of impurities.

Abstract: The present invention relates to a system for carrying electrical energy in connections made by means of underground cables. In particular, it relates to a method of laying cables and a trench filler having a low thermal resistivity, used for laying underground cables for carrying electrical energy. More particularly, it relates to the use of an inert filler to be disposed in an area around the cables or the parts of the system, such as joints, which are disposed underground.