Prysmian Cavi E Sistemi Energia S.r.l.

Pirelli Cavi E Sistemi S.p.a.

Pirelli Cavi S.p.a.

Pirelli & C. S. P. A.

Dsm N.v.

Prysmian S.p.a.

Alessandro Ginocchio

Massimo Pizzorno

Enrico Maria Consonni

Mauro Maritano

Giovanni Brandi

Feliciano Cecchi

Massimiliano Pavan

Davide Ceschiat

Enrico Consonni

Francesco Della Corte

Flavio Sangalli

Luis Sales Casals

Paolo Arturo Presa

Johannes Adrianus Van Eekelen

Adrianus G M Abel

Adrianus Gijsbertus Maria Abel

Gouke Dirk Jan Geus

Nunzio Romanini

Luciano Lepri

Albert A Vries De

Gouke D J Geus

Johannes C Burg Van Den

Johannes A Eekelen Van

Fabio Bau'

Johannes Cornelis Van Den Burg

Albert Allan De Vries

Fabio Bau′

Agusti Valls Prats

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:  in which Vis the volume of the water swellable yarn after swelling upon contact with water; Vis the total free volume in the retaining element; k is a constant&#x2267;180; R is a constant&#x2267;1.4; and Vis 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.

Water-blocked optical cable and process for the production thereof

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 (S) 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.

Apparatus for manufacturing an optical cable and cable so manufactured

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 (S) 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.

Method and apparatus for manufacturing an optical cable and cable so manufactured

A method for manufacturing an optical cable for communication includes at least one micromodule, said micromodule being blocked with respect to the propagation of water. The method includes the steps of providing at least one optical fiber; embedding the at least one optical fiber in a pseudoplastic filling compound having a viscosity of 3 Pa&#xb7;s to 30 Pa&#xb7;s, preferably 7 Pa&#xb7;s to 25 Pa&#xb7;s at a shear rate of 10 sand at a temperature of 100&#xb0; C., and a cross-over lower than 30 Hz, preferably 5 Hz to 25 Hz, at a temperature of 100&#xb0; C.; and extruding a retaining element made of a thermoplastic polymeric composition around the at least one optical fiber so embedded in the filling compound to obtain a micromodule.

Water-resistant optical cable and manufacturing method

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: in which Vis the volume of the water swellable yarn after swelling upon contact with water; Vis the total free volume in the retaining element; k is a constant &#x2267;180; R is a constant &#x2267;1.4; and Vis 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.

A telecommunication fiber optic cable for gas pipeline application has a built-in leakage detecting device. The cable has an optical core including a number of telecommunication optical fibers, an outer jacket covering the optical core, and one or more gas leakage detector optical fibers. One or more gas leakage detector optical fibers are enclosed within the outer jacket. Preferably, the cable has a linearly extending rod reinforcing system having strength rods that force the cable to bend in a preferential bending place. Preferably, the leakage detector optical fibers are located at, or close to, a plane that is substantially orthogonal to the preferential bending plane and passing through the cable neutral axis.

Telecommunication optical cable for gas pipeline applications having built-in leakage detecting device

An optical cable for communication includes at least one micromodule, wherein the micromodule is blocked with respect to the propagation of water. The at least one micromodule includes at least one optical fiber, a retaining element for housing the at least one optical fiber, and a thixotropic filling compound arranged within the retaining element. The filling compound is thixotropic, has a viscosity higher than or equal to 700 Pa&#xb7;s at zero shear rate and at a first temperature of 20&#xb0; C., a loss modulus G&#x2033; lower than or equal to 3000 MPa at 1 Hz and at a second temperature of &#x2212;45&#xb0; C., and is compatible with the retaining element.

Optical cable for communication

An optical fiber cable has a highly reduced diameter. The cable has a central strength member; a number of tubes containing loosely arranged optical fibers, each tube having a thickness, and each optical fiber having a coating; and a protective outer jacket, wherein the filling coefficient of optical fibers in at least one loose tube is &#x2267;45&#xb0;/0. The tubes are made of a material having an elasticity modulus &#x2267;700 MPa; and the optical fibers are SM-R fibers having a microbending sensitivity &#x2266;4.0 dB&#xb7;km/g&#xb7;mmat a temperature of about &#x2212;30&#xb0; C. to +60&#xb0; C. at about 1550 nm.

Telecommunication loose tube optical cable with reduced diameter

A telecommunication optical fiber cable and in particular a reduced diameter optical cable with improved installation features for use in the end part of an access telecommunication network. The optical fiber cable has a number of optical fibers; at least a core tube containing the optical fibers; a jacket surrounding the core tube; and at least one strength rod spaced from the central axis, the cable having a twisting stiffness G*J, wherein G is the elastic shear modulus; and Jis the polar moment of inertia of a cable section, wherein the twisting stiffness G*Jis lower than or equal to 0.10 Nm, preferably lower than or equal to 0.05 Nm, and more preferably lower than or equal to 0.02 Nm. The cable is profitably installable by a blown method.

Dielectric optical fiber cable having improved installation features

An optical cable having an optical core with a strength member and optical fibers embedded in a thermoplastic material. The optical core has a joint section having substantially the same diameter as the one of the optical core. The joint section has a jointed strength member and a plurality of spliced optical fibers, the jointed portion of the strength member and the spliced portion of the optical fibers being embedded into a cured polymeric material. A method for manufacturing an optical core is also disclosed.

Telecommunication cable comprising a jointed optical core and method for jointing said core

An optical cable having at least one element for the transmission of optical signals and a structure that is able to protect the at least one element. The structure is a multilayer structure and is arranged in a position radially external to the at least one element and has a) at least one first covering layer of polymeric material in a position radially external to the at least one element; b) at least one covering layer of foamed polymeric material in a position radially external to the at least one first covering layer, and c) at least one second covering layer of polymeric material in a position radially external to the at least one covering layer of foamed polymeric material. The foamed polymeric material has a density between 0.3 and 0.7 kg/dmand tensile modulus at 20&#xb0; C. between 300 and 700 MPa.

Optical cable provide with a mechanically resistant covering

A telecommunication optical cable has a number of optical fibers; at least a microsheath loosely containing the optical fibers, the at least one microsheath loosely containing the optical fibers therein forming at least one corresponding microbundle, wherein the optical fibers are stranded according to an open helix trajectory.

High count telecommunication optical cable with controlled fiber length method and apparatus for manufacturing the same

Optical fiber ribbon having an optical fiber with a radiation curable internal coating and a radiation curable colored coating disposed to surround the internal coating, and a radiation curable matrix material surrounding one or more of the optical fibers to form a ribbon, in which: the colored coating has a degree of adhesion to the inner coating which is higher than the degree of adhesion to the matrix material; and the optical fiber in the optical fiber ribbon shows, upon aging of the ribbon for at least two weeks in water at 60&#xb0; C., an increase in the attenuation of the transmitted signal at 1550 nm of less than 0.05 db/km with respect to the attenuation of the assembled optical fiber measured before aging.

Colored optical fiber and optical fiber ribbon assembly containing said fiber

The invention relates to a radiation curable colored coating composition for coloring a coated optical fiber wherein the coating, when disposed and cured to surround an optical fiber coated with an internal coating, and when said colored fiber is coated with a matrix material and assembled into an optical fiber ribbon, said colored coating has a degree of adhesion to the internal coating which is higher than the degree of adhesion to the matrix material and said optical fiber assembled into said optical fiber ribbon shows, upon aging for at least two weeks in water at 60&deg; C., an increase in the attenuation of the transmitted signal at 1550 nm of less than 0.05 db/km with respect to the attenuation of the assembled optical fiber measured before aging. The invention also relates to said colored coating composition when used in an optical fiber ribbon.

Radiation curable colored coating composition

A submarine optical cable resistant to a longitudinal flow of water accidentally penetrated inside it and a method for controlling the longitudinal flow of water inside the cable. The cable has a longitudinal cavity disposed along a deformable elongated hollow body. The longitudinal cavity is suitable dimensioned so that the head losses of the water flowing through the cavity are lower than the head losses of the water flowing inside the buffer tubes. Thus, in case of accidental ingress of water inside the submarine cable, the water flow inside the buffer tubes is prevented from reaching long penetration lengths by the hydrostatic pressure of the water inside the longitudinal cavity acting onto the outer surface of the buffer tube.

Growing community of inventors

Sesto San Giovanni, Italy

Alessandro Ginocchio