Abstract: A loose tube element including a plastic sheath containing a grease-like material and an optical fiber or bundle of optical fibers or a ribbon of optical fibers is pulled from an extruder crosshead through a cooling bath and around a constant speed capstan. The loose tube element travels around the constant speed capstan a number of times and as it exits the capstan it is subject to a tensile force provided by a variable torque control capstan. The tensile force causes elongation of the plastic sheath, causes the optical fiber to be pulled taut and thereby controls the ratio of fiber length to sheath length within the loose tube element. While subjected to the tensile force, the element is subsequently cooled, causing the elongation of the plastic sheath to become permanent and thus fixing the fiber-to-sheath length ratio.

Abstract: A steam resistant optical fiber cable for use adjacent underground steam ducts in metropolitan locations. The optical fiber cable comprises polyethersulfone loose tubes for enhanced hydrolytic stability and a welded aluminum tube swaged over the fiber core to provide moisture imperviousness. The welded aluminum tube is bonded to the fiber core with an intermediate resin barrier layer to provide resistance to repeated cyclic flexing of the cable.

Abstract: A cable shielding method and apparatus are disclosed wherein adhesive 42 is applied to a strip 40 of shielding material within a shield forming die 20 as the strip 40 is being formed about a cable core 10 with an overlapped shield seam.

Abstract: A cable which is capable of being made in a large pair size and yet which has excellent mechanical properties that maintain its integrity notwithstanding extremes in temperature during installation and shipping as well as during the rigors of installation includes a sheath system having a corrugated steel outer shield that is adhesively bonded to a plastic jacket. The corrugated steel shield which is formed to have a longitudinal overlapped seam that is preferably unsealed encloses an aluminum inner shield that in turn encloses a multiconductor core. Advantageously, the sheath system includes a plastic jacketing material which is capable of resisting biaxial stresses which are aggravated in a bonded sheath system. This results in jacket integrity about the longitudinal seam of the outer shield notwithstanding a notched cross-section and an unsupported bridged portion of the plastic jacket adjacent to the seam.

Abstract: A cable which is capable of being made in a large pair size and yet which has excellent mechanical properties that maintain its integrity notwithstanding extremes in temperature during installation and shipping as well as during the rigors of installation includes a sheath system having a corrugated steel outer shield that is adhesively bonded to a plastic jacket. The corrugated steel shield which is formed to have a longitudinal overlapped seam that is preferably unsealed encloses an aluminum inner shield that in turn encloses a multiconductor core. Advantageously, the sheath system includes a plastic jacketing material which is capable of resisting biaxial stresses which are aggravated in a bonded sheath system. This results in jacket integrity about the longitudinal seam of the outer shield notwithstanding a notched cross-section and an unsupported bridged portion of the plastic jacket adjacent to the seam.

Abstract: Methods and apparatuses are disclosed for extruding tubular jackets of uniform radial thicknesses about cables employing a diverter tube assembly 10 that provides a divergent flow path for a plastic fluid from diametrically opposite channel orifices 46 to a tubular confluence. The diverter tube circumference is between 22 and 50 times the prespread width of each channel orifice while the axial to lateral spread ratio of the divergent flow path is between 1:2 tangent 30.degree. and 1:2 tangent 40.degree..

Abstract: A waterproof shielded cable is disclosed having a metallic shield formed with a longitudinal seam surrounding a core. A strip of material overlays the metallic shield seam with side edges located to each side of the seam. An extruded plastic jacket overlays the metallic shield and strip of material with the jacket being in intimate contact with the shield and with a principle surface of the strip of material but spaced from the strip side edges.A method is also disclosed for manufacturing a shielded cable which comprises the step of wrapping sheet metal about a cable core with the sheet metal edges overlapped to form a shield with a longitudinal seam. The shield seam is overlayed with a strip of material of a type characterized by being shrinkable when heated above a predetermined temperature, and with the strip edges straddling the shield seam. A plastic jacket is extruded onto the shielded core and strip of material at a temperature in excess of the predetermined temperature.