Abstract: It is disclosed a process and an apparatus for manufacturing a figure of eight cable. An extrusion head has separate extrusion dies extruding in parallel a first and second outer sheath around a first and second core, respectively, so as to provide two separate cable elements having respective longitudinal axes laying in a first plane. While the outer sheaths are in a softened state, the cable elements are passed in parallel through a twisting die which causes their longitudinal axes to lay in a second plane forming a predetermined twisting angle with respect to the first plane. This twisting causes the outer sheaths to join together, thereby forming a figure of eight cable.

Abstract: It is disclosed a figure of eight cable comprising a first cable element comprising a first core enclosed by a first outer sheath, a second cable element comprising a second core enclosed by a second outer sheath and a web joining the first and second outer sheaths so as to provide the cable with a major plane of symmetry X which comprises the longitudinal axes of the first and second cable elements. The cable also comprises at least one strength member embedded within the first or second outer sheath. All the strength members of the cable are substantially located on the major plane of symmetry X of the cable.

Abstract: An optical cable includes an optical module which includes first optical fibers and a first retaining element arranged about the first optical fibers. The module also includes second optical fibers arranged about the first retaining element, the second optical fibers being arranged on at least one circumference concentric with the first retaining element. The module also includes a second retaining element arranged about the second optical fibers, which is also substantially coaxial with the first retaining element. This optical module with coaxial retaining elements and fibers has a particularly high fiber density, while preserving the possibility to uniquely identify all the fibers.

Abstract: It is disclosed a figure of eight cable comprising a first cable element comprising a first core enclosed by a first outer sheath, a second cable element comprising a second core enclosed by a second outer sheath and a web joining the first and second outer sheaths so as to provide the cable with a major plane of symmetry X which comprises the longitudinal axes of the first and second cable elements. The cable also comprises at least one strength member embedded within the first or second outer sheath. All the strength members of the cable are substantially located on the major plane of symmetry X of the cable.

Abstract: It is disclosed a process and an apparatus for manufacturing a figure of eight cable. An extrusion head has separate extrusion dies extruding in parallel a first and second outer sheath around a first and second core, respectively, so as to provide two separate cable elements having respective longitudinal axes laying in a first plane. While the outer sheaths are in a softened state, the cable elements are passed in parallel through a twisting die which causes their longitudinal axes to lay in a second plane forming a predetermined twisting angle with respect to the first plane. This twisting causes the outer sheaths to join together, thereby forming a figure of eight cable.

Abstract: An optical cable includes an optical core and an external sheath surrounding the optical core. The external sheath includes a first material having a first, higher fracture toughness and a second material having a second, lower fracture toughness. The first and second materials are arranged so that the second, lower fracture toughness material is accessible from outside the cable along at least one longitudinally extending area of the sheath outer surface. For accessing the optical core of the cable, a short longitudinal cut, namely, few centimeters, is made with a blade in the accessible second, lower fracture toughness material. Then, its cut edges are pulled apart by hand. The pulling force causes the lower fracture toughness material to fracture, thereby propagating the initial short cut longitudinally along the sheath through its whole thickness.

Abstract: An optical cable includes an optical module which includes first optical fibers and a first retaining element arranged about the first optical fibers. The module also includes second optical fibers arranged about the first retaining element, the second optical fibers being arranged on at least one circumference concentric with the first retaining element. The module also includes a second retaining element arranged about the second optical fibers, which is also substantially coaxial with the first retaining element. This optical module with coaxial retaining elements and fibers has a particularly high fiber density, while preserving the possibility to uniquely identify all the fibers.

Abstract: An optical cable includes an optical core and sheath enclosing the optical core. The optical core includes a number of optical units having respective colors and being wound about a longitudinal axis of the cable. The sheath includes at least one non opaque longitudinal section through which a sequence of colors of the optical units is visible from outside the cable. The color sequence acts as an identifier for the cable. The cable may therefore be easily identified (e.g. amongst other cables laid down within the same duct) by a simple visual inspection of the cable's inner structure through the non opaque section(s) of its external sheath.

Abstract: An optical cable includes an optical core and an external sheath surrounding the optical core. The external sheath includes a first material having a first, higher fracture toughness and a second material having a second, lower fracture toughness. The first and second materials are arranged so that the second, lower fracture toughness material is accessible from outside the cable along at least one longitudinally extending area of the sheath outer surface. For accessing the optical core of the cable, a short longitudinal cut, namely, few centimetres, is made with a blade in the accessible second, lower fracture toughness material. Then, its cut edges are pulled apart by hand. The pulling force causes the lower fracture toughness material to fracture, thereby propagating the initial short cut longitudinally along the sheath through its whole thickness.

Abstract: An optical cable includes an optical core and sheath enclosing the optical core. The optical core includes a number of optical units having respective colors and being wound about a longitudinal axis of the cable. The sheath includes at least one non opaque longitudinal section through which a sequence of colors of the optical units is visible from outside the cable. The color sequence acts as an identifier for the cable. The cable may therefore be easily identified (e.g. amongst other cables laid down within the same duct) by a simple visual inspection of the cable's inner structure through the non opaque section(s) of its external sheath.