Flame retardant duct having embedded strength elements

Abstract

Embodiments of the disclosure relate to a duct for an optical fiber cable. The duct includes a tubular wall having an inner surface and an outer surface. The inner surface defines a longitudinal bore. A plurality of strength elements is disposed within the tubular wall. The plurality of strength elements is formed from yarns that are not combustible at a temperature below 900° C. Also disclosed are embodiments of a method of forming such a duct. In the method, a flame retardant polymeric composition is extruded to form the tubular wall, and the plurality of strength elements are embedded in the tubular wall. It is expected that the combination of an optical fiber cable having a flame retardant rating and such a duct will maintain the flame retardant rating when the optical fiber cable is disposed within the longitudinal bore of the duct.

Dependencies are inferred from the claim text.