摘要:
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.
摘要:
A process for manufacturing a cable includes the steps of conveying at least one conductor to an extruder apparatus; extruding an insulating coating layer radially external to the at least one conductor; longitudinally folding a metal tape around the extruded insulating coating layer, the metal tape bearing at least one adhesive coating layer in a radially external position; and extruding at least one continuous coating layer of at least one polyamide or a copolymer thereof around and in contact with the folded metal tape. The step of extruding the at least continuous coating layer is carried out at a draw down ratio not higher than 2.5, preferably, 1.2 to 2.0.
摘要:
The present invention relates to a manufacturing process of a multipolar cable comprising at least one pair of cores, each core comprising at least one conductive element and at least one layer of electrical insulation in a position which is radially external to said at least one conductive element. This process comprises the steps of: a) assembling said at least one pair of cores so as to form an assembled element having a plurality of interstitial zones between said cores, and b) depositing by co-extrusion an expandable polymeric material in a position which is radially external to said cores so as to fill said interstitial zone and to form a filling layer of substantially zone and to form a filling layer of substantially circular transverse cross section, and at least one containment layer of polymeric, and at least one containment layer of polymeric material in a position radially external to said filling layer. The present invention also relates to a multipolar cable obtained from said process.
摘要:
A cable for use in a predetermined voltage class, has a conductor; an insulating layer surrounding the conductor, the insulating layer having a thickness selected to provide a predetermined electrical stress when the cable is operated at a nominal voltage in said predetermined voltage class; and a protective element around the conductor having a thickness and mechanical properties selected to provide a predetermined impact resistance capability, the protective element having at least one expanded polymeric layer. The insulating layer thickness and the protective element thickness are selected in combination to minimize the overall cable weight while preventing a detectable insulating layer damage upon impact of 50 J energy. A method for designing a cable is also disclosed.
摘要:
A device including at least one gripping member, rotatably mounted about an axis Z-Z, adapted to hold at least one end of at least one elongated element for chemical vapour deposition for forming a preform. The device includes at least one burner being mobile along a direction substantially parallel to the axis Z-Z and adapted to deposit, on the elongated element, a chemical substance for forming a preform, and at least one suction element arranged on the opposite side of the burner on a portion of a wall of the device on the opposite side of the gripping member from the burner. At least one air suction member, mobile along direction Z, is provided with motion synchronous with respect to the burner. The wall with the air suction member has a pair of respective upper and lower tapes rigidly associated with the burner.
摘要:
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.
摘要:
Optical fiber having a glass portion; at least one protective coating of thermoplastic material having at least one thermoplastic elastomer; the thermoplastic material having the following characteristics: a modulus of elasticity value at +25° C. lower than 150 MPa, preferably at least 10 Mpa, more preferably higher than 20 Mpa, and a Vicat point higher than 85° C., preferably higher than 120° C., more preferably lower than 350° C. Preferably, the coating is a single protective coating directly positioned onto the glass portion.
摘要:
A water-resistant telecommunication cable is disclosed comprising a solid and compact element surrounding at least one optical transmitting element, wherein the element is made from a vinyl alcohol/vinyl acetate copolymer having a hydrolysis degree of about 60% to about 95% and a polymerization degree higher than about 2,500; at least a first solid plasticizer having a melting point between 50° and 110° C., and a second solid plasticizer having a melting point equal or higher than 140° C., in an amount of about 10–30 and 1–10 parts by weight per hundred parts by weight of the copolymer, respectively; the water-soluble polymer material showing: a complex modulus (G*) equal to or higher than 2.5 106 Mpa; a ratio of the viscous modulus to the elastic modulus (tan δ) equal to or lower than 2.30; and a glass transition temperature (Tg) of about 20° to about 35° C.
摘要:
An apparatus for disposing a tubular covering sleeve for electric-cable joints on a supporting element may include a support for the tubular covering sleeve; a pair of expanders; driving means configured to introduce the expanders into respective ends of the tubular covering sleeve and to cause radial expansion of the tubular covering sleeve; and devices for disposing the tubular covering sleeve in a radially expanded condition on the supporting element. The expanders may be configured to be placed in substantially coaxial positions relative to the tubular covering sleeve at the respective ends of the tubular covering sleeve.
摘要:
An apparatus and method for chemical deposition on a rod member having a support structure for supporting the rod member substantially coaxial to a deposition axis; a burner for depositing chemical substances on the rod member; and a rotation device for imparting a rotation motion to the rod member. The rotation device has a joint member of a type suitable to transmit torque between two misaligned members, for example, a double universal joint or a flexible joint, positioned between a motor and a rod gripping member.