摘要 |
Disclosed is a composite overhead cable structure having high seal properties, comprising a metallic pipe, at least one layer of stranded metallic elongated conductor surrounding the outer periphery of the pipe, and an optical fiber cable disposed within and extending throughout the length of the pipe, wherein the metallic pipe comprises at least two metallic pipe sections which are arranged in alignment and connected at their respective confronting terminals having contours complementary to each other and wherein the metallic pipe has a specific structure of connection between the mutually adjacent pipe sections, such that a longitudinal through-weld extends along the entire length of the metallic pipe and such that a connecting turning weld extends between first and second different points on the longitudinal through-weld of the metallic pipe so as to turn around the axis of said metallic pipe, the first and second points being positioned at a distance which satisfies a specific relationship. The welded metallic pipe has no weld defects in the longitudinal through-weld thereof so that the metallic pipe has excellent seal properties and therefore, the composite overhead cable structure of the present invention is free from the danger that rain water or the like enters the pipe and adversely affects the optical fiber cable.
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