Abstract: Apparatus for applying traction to an elongate cylindrical element produced by fusion of an end portion of a preform of glass material, in which a traction device is capable of being connected to a portion of the elongate cylindrical element to provide traction of the elongate cylindrical element along an axis. A device for the rotation of the elongate cylindrical element applies a twist to the elongate cylindrical element about the axis simultaneously with the traction.

Abstract: An optical cable for communication includes at least one retaining element blocked with respect to the water propagation as well as a process for manufacturing such an optical cable. The optical cable includes, in addition to the retaining element, at least two transmission elements housed within the retaining element and a water swellable yarn housed within the retaining element. The water swellable yarn is selected according to the following equation: V w V TF = k V t + R ( I ) in which Vw is the volume of the water swellable yarn after swelling upon contact with water; VTF is the total free volume in the retaining element; k is a constant?180; R is a constant?1.4; and Vt is the free volume per each transmission element. Advantageously, the optical cable is water-blocked and the water swellable yarn does not induce microbending effects on the transmission elements.

Abstract: A method of coating the junction area between elongated elements, in particular between electric cables. This method includes the steps of: arranging a rigid tubular support having two axially separable tubular halves; mounting an elastic tubular sleeve in an elastically radially expanded condition on an outer surface of the support; interposing a lubricating material between the support and sleeve; arranging a circumferentially continuous sealing element between the halves to prevent the lubricant from percolating between the halves; positioning the support around the junction area; and moving the halves apart from each other to enable the sleeve to collapse on the junction area. A device for coating the junction area between elongated elements and a method of making the device and a joint for electric cables.

Abstract: An electric power cable contains a core and a jacket forming the exterior of the cable. The jacket is formed by extruding a first layer and a second layer over a plurality of concentric neutral elements, substantially encapsulating these elements. At least the first layer is an expanded polymeric material, by having its density reduced through the use of a foaming agent during extrusion. The second layer, which may also be expanded, is extruded around the first layer. The expanded polymeric material makes stripping the jacket easier, minimizes indentations in the cable's insulation layers, lightens the cable, and increases the cable's flexibility.

Abstract: 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.

Abstract: Process for manufacturing a cable comprising the following steps:(a) conveying at least one conductor to an extruder apparatus;(b) extruding an insulating coating layer radially external to said at least one conductor; (c) longitudinally folding a metal tape around said extruded insulating coating layer, said metal tape bearing at least one adhesive coating layer in a radially external position; (e) extruding at least one continuous coating layer comprising at least one polyamide or a copolymer thereof around and in contact with said folded metal tape; wherein the step (e) is carried out at a draw down ratio (DDR) not higher than 2.5, preferably of from 1.2 to 2.0.

Abstract: A process for manufacturing a self-extinguishing cable including at least one transmissive element and at least one flame-retardant coating in a position radially external to the at least one transmissive element, wherein the at least one coating includes an expanded flame-retardant polymeric material having (a) at least one expandable polymer; (b) at least one expanding agent; (c) at least one flame-retardant inorganic filler, in an amount of 100 parts by weight of 250 parts by weight with respect to 100 parts by weight of the at least one expandable polymer. The process includes the following steps: (i) feeding the flame-retardant polymeric material to an extruding apparatus, therein melting and mixing it; (ii) passing the flame-retardant polymeric material obtained in step (i) through at least one static mixer; and (iii) depositing by extrusion the flame-retardant polymeric material obtained in step (ii) onto the at least one transmissive element conveyed to the extruding apparatus.

Abstract: Apparatus for applying traction to an elongate cylindrical element produced by fusion of an end portion of a preform of glass material, in which a traction device is capable of being connected to a portion of the elongate cylindrical element to provide traction of the elongate cylindrical element along an axis. A device for the rotation of the elongate cylindrical element applies a twist to the elongate cylindrical element about the axis simultaneously with the traction.

Abstract: 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.

Abstract: A process for manufacturing an electric cable including at least one core including a conductor and an insulating coating surrounding the conductor includes the steps of: providing a polyolefin material, a silane-based cross-linking system and a foaming system including at least one exothermic foaming agent in an amount of 0.1% to 0.5% by weight with respect to the total weight of the polyolefin material; forming a blend with the polyolefin material, the silane-based cross-linking system and the foaming system; and extruding the blend on the conductor to form the insulating coating. An electric cable includes at least one core consisting of a conductor and an insulating coating surrounding the conductor and in contact therewith, the insulating coating consisting of a layer of expanded, silane-cross-linked polyolefin material having an expansion degree of 3% to 40%.

Abstract: Apparatus for applying traction to an elongate cylindrical element produced by fusion of an end portion of a preform of glass material, in which a traction device is capable of being connected to a portion of the elongate cylindrical element to provide traction of the elongate cylindrical element along an axis. A device for the rotation of the elongate cylindrical element applies a twist to the elongate cylindrical element about the axis simultaneously with the traction.

Abstract: A method of coating the junction area between elongated elements, in particular between electric cables. This method includes the steps of: arranging a rigid tubular support having two axially separable tubular halves; mounting an elastic tubular sleeve in an elastically radially expanded condition on an outer surface of the support; interposing a lubricating material between the support and sleeve; arranging a circumferentially continuous sealing element between the halves to prevent the lubricant from percolating between the halves; positioning the support around the junction area; and moving the halves apart from each other to enable the sleeve to collapse on the junction area. A device for coating the junction area between elongated elements and a method of making the device and a joint for electric cables.

Abstract: An apparatus for applying an elastic tubular sleeve onto a splicing region between at least one pair of cables, wherein the tubular sleeve is supported in a radially expanded condition on at least one supporting element, may include axial-movement devices configured to axially move the at least one supporting element relative to the tubular sleeve at an adjustable speed, so as to cause a radial elastic shrinkage of the tubular sleeve capable of inducing an axial ejection thrust on the at least one supporting element, and counter devices configured to counteract the axial ejection thrust induced by the elastic shrinkage of the tubular sleeve.

Abstract: A burner for a vapour deposition process has a central nozzle for ejecting a glass precursor material, at least a crown of nozzles surrounding said central nozzle for ejecting a flame reactant, and a circular nozzle between said central nozzle and said crown of nozzles for ejecting an innershield gas, wherein the central nozzle has a concave shape in a cross section in the axial plane and, preferably, a symmetry about an axial plane.

Abstract: A method of splicing first and second cables may include providing an elastic tubular sleeve, supported by at least one supporting element, in a radially expanded condition; arranging the sleeve in the radially expanded condition around one cable; connecting the cables to obtain a splicing region; positioning the sleeve in the radially expanded condition around the splicing region; axially moving the at least one supporting element relative to the sleeve to cause radial elastic shrinkage of the sleeve capable of inducing axial ejection thrust on the at least one supporting element; counteracting the axial ejection thrust; and adjusting axial movement speed of the at least one supporting element to adapt the axial movement speed to a speed of the elastic shrinkage. Counteracting the axial ejection thrust may include applying axial reaction force to one end of the at least one supporting element axially projecting from the sleeve.

Abstract: A method for manufacturing a cable, the cable including at least one transmissive element and at least one coating layer made of a polymeric material and arranged at a radially outer position with respect to the transmissive element. The method includes the steps of: a) feeding the polymeric material to an extrusion apparatus including an extrusion head, the extrusion head including a male die; a female die coaxially arranged with respect to the male die; a conveying channel, at least one portion of which is defined between the male die and the female die; and b) controlling a cross-sectional area of the at least one portion of the conveying channel in response to a detected quantity, the quantity being caused to vary during the manufacturing of the cable as a function of the actual extrusion speed. An extrusion apparatus for carrying out the process.

Abstract: A method for producing an optical fiber preform. Glass soot particles are formed by jetting and combusting a gaseous glass-forming material and a fuel gas from a burner in the presence of oxygen. The glass soot particles are deposited on a deposition rod while rotating the deposition rod about its axis and reciprocating the burner in parallel to the deposition rod so as to form the preform and varying at least one of the translation velocity of the burner and the rotation velocity of the rod so as to obtain a predetermined radial soot density distribution in the preform.

Abstract: An apparatus (100) and method cleans a batch of pellets or granules prior to use in an extrusion process. Loose contaminants having material characteristics that are undersired for the extruded product are first removed (110) from the batch using a deduster. The deduster may also remove uncontaminated fines and fluff from the batch. Pellets that are defective or otherwise undersired for the extrusion process as well as other loose particle contaminants can then be efficiently detected and removed (120) without the risks of fines clogging the apparatus or shielding the detection process. Magnets may help remove (130) particulates of ferrous material before or after the removal (120) of defective pellets. The resulting batch of pellets helps to produce extruded materials of higher quality, such as insulation material in electrical cables.

Abstract: A method and apparatus for manufacturing an optical cable comprising at least one metal tube housing at least one optical fiber and having a predetermined excess fiber length (EFL) is described. In this method the metal tube is plastically deformed and shortened by a predetermined amount (St) greater than the predetermined EFL and is plastically deformed after shortening to provide a controlled elongation thereof so as to reach the predetermined excess fiber length. An optical cable so manufactured has a local excess fiber length (EFL) varying of or less than 0.2% along the longitudinal extension of the cable with respect to an average EFL of the cable.

Abstract: A method and device for manufacturing a preform for optical fibers through chemical deposition on a substrate for deposition arranged vertically is described, comprising a chemical deposition chamber including at least one gripping member rotatably mounted about an axis Z-Z and adapted to hold at least one end of at least one elongated element constituting a substrate for chemical deposition for the formation of a preform for optical fibers. The chamber includes, moreover, at least one burner which is mobile along a direction Z substantially parallel to said axis Z-Z and adapted to deposit, on said at least one elongated element, a chemical substance for the formation of a preform and at least one suction element for collecting exhaust chemical substances, said at least one suction element being arranged on the opposite side to said at least one burner with respect to said axis Z-Z and being mobile along said direction Z.