Method for making high strain aerial fiber optic cable

Claim 1

A method of making an all-dielectric self-supporting fiber optic aerial cable of a type comprising a core including at least one optical transmission fiber adjacent to a central strength member and surrounded by an outer jacket, and a radially spaced-apart strength member, said radially spaced-apart strength member serving as a primary strength element and said central strength member serving as a secondary strength element for said cable, wherein a pistoning movement of said secondary strength element within said cable core when under cable strain is minimized, said method comprising the steps of: calculating a required degree of mechanical coupling between said primary and secondary strength elements according to the equation: ##EQU3## wherein Kc=required degree of mechanical coupling between primary and secondary strength elements; XO=minimum excess cable length between support structure and a splice housing; T=maximum tension on system; [EA]m=Young's Modulus-area product of primary element(s); [EA]c=Young's Modulus-area product of secondary element(s); αm=thermal coefficient of primary element; αc=thermal coefficient of secondary element; and Δt=temperature change: operation-manufacture; selecting suitable elements in making said fiber optic cable, including at least an adhesive-type filling compound for said cable core, so as to make said fiber optic cable with a Kc value equal to or greater than said calculated Kc value; and forming said fiber optic cable from said selected elements, said fiber optic cable comprising a core including at least one optical transmission fiber adjacent to a central strength member and surrounded by an outer jacket, a radially spaced-apart strength member, and an adhesive-type cable core filling compound.

Claim 2

A method of making an all-dielectric self-supporting fiber optic aerial cable of a type comprising a core including at least one optical transmission fiber adjacent to a central strength member and surrounded by an outer jacket, and a radially spaced-apart strength member, said radially spaced-apart strength member serving as a primary strength element and said central strength member serving as a secondary strength element for said cable, wherein a pistoning movement of said secondary strength element within said cable core when under cable strain is minimized, said method comprising the steps of: calculating a required degree of mechanical coupling between said primary and secondary strength elements according to the equation: ##EQU3## wherein Kc=required degree of mechanical coupling between primary and secondary strength elements; XO=minimum excess cable length between support structure and a splice housing; T=maximum tension on system; [EA]m=Young's Modulus-area product of primary element(s); [EA]c=Young's Modulus-area product of secondary element(s); αm=thermal coefficient of primary element; αc=thermal coefficient of secondary element; and Δt=temperature change: operation-manufacture; selecting suitable elements in making said fiber optic cable, including at least an adhesive-type filling compound for said cable core, so as to make said fiber optic cable with a Kc value equal to or greater than said calculated Kc value; and forming said fiber optic cable from said selected elements, said fiber optic cable comprising a core including at least one optical transmission fiber adjacent to a central strength member and surrounded by an outer jacket, a radially spaced-apart strength member, and an adhesive-type cable core filling compound.

Claim 15

A method of making an all-dielectric, self-supporting fiber optic aerial cable of a Figure-8 type comprising a core including at least one optical transmission fiber adjacent to a central strength member and surrounded by an outer jacket, and a supporting messenger therefor, said messenger serving as a primary strength element and said central strength member serving as a secondary strength element for said cable, wherein a pistoning movement of said secondary strength element within said cable core under cable strain is minimized, said method comprising the steps of: calculating a required degree of mechanical coupling between said primary and secondary strength elements according to the equation: ##EQU4## wherein: Kc=required degree of mechanical coupling between primary and secondary strength elements; XO=minimum excess cable length between cable support structure and a splice housing; T=maximum tension on system; [EA]m=Young's Modulus-area product of primary element(s); [EA]c=Young's Modulus-area product of secondary element(s); αm=thermal coefficient of primary element; αc=thermal coefficient of secondary element; and Δt=temperature change: operation-manufacture; selecting suitable elements in making said fiber optic cable, including an adhesive-type filling compound for said cable core, so as to make said fiber optic cable with a Dc value equal to or greater than said calculated Kc value; and forming said fiber optic cable from said selected elements, said fiber optic cable comprising a core including at least one optical transmission fiber adjacent to a central strength member and surrounded by an outer jacket, a supporting messenger, and an adhesive-type cable core filling compound.

Claim 16

A method of making an all-dielectric, self-supporting fiber optic aerial cable of a Figure-8 type comprising a core including at least one optical transmission fiber adjacent to a central strength member and surrounded by an outer jacket, and a supporting messenger therefor, said messenger serving as a primary strength element and said central strength member serving as a secondary strength element for said cable, wherein a pistoning movement of said secondary strength element within said cable core under cable strain is minimized, said method comprising the steps of: calculating a required degree of mechanical coupling between said primary and secondary strength elements according to the equation: ##EQU4## wherein: Kc=required degree of mechanical coupling between primary and secondary strength elements; XO=minimum excess cable length between cable support structure and a splice housing; T=maximum tension on system; [EA]m=Young's Modulus-area product of primary element(s); [EA]c=Young's Modulus-area product of secondary element(s); αm=thermal coefficient of primary element; αc=thermal coefficient of secondary element; and Δt=temperature change: operation-manufacture; selecting suitable elements in making said fiber optic cable, including an adhesive-type filling compound for said cable core, so as to make said fiber optic cable with a Dc value equal to or greater than said calculated Kc value; and forming said fiber optic cable from said selected elements, said fiber optic cable comprising a core including at least one optical transmission fiber adjacent to a central strength member and surrounded by an outer jacket, a supporting messenger, and an adhesive-type cable core filling compound.