Microducts are small ducts for the installation of small microduct fibre optic cables.They have a size ranging from typically 3 to 16 mm and are installed as bundles in larger ducts.Microducts are typically small-diameter, flexible, or semi-flexible ducts designed to provide clean, continuous, low-friction paths for placing optical cables that have relatively low pulling tension limits. As stated in industry requirements document Telcordia. GR-3155, Generic Requirements for Microducts for Fibre Optic Cables, microduct products are expected to:

    • Be compatible with existing construction designs and building configurations for both riser- and plenum-rated applications, including cable blowing apparatus.
    • Allow cables to be safely deployed through pull lines or strings using less than 50 lbs of force, and through cable blowing techniques at typical deployment speeds of 100-200 feet per minute.

Ducts can be purchased with a variety of options or features. One such enhancement is pre-lubrication. Pre-lubricated ducts may be either permanently impregnated with anti-friction compounds or coated with liquid lubricant during manufacture. This may or may not eliminate the need for supplementary lubrication when pulling cable into the duct. Before using a supplementary lubricant with a pre-lubricated duct, the user should check with the manufacturer to determine if the added lubricant is compatible with the pre-lubricated surface of the duct. Failure to do this may result in the cable seizing up rather than reducing the friction coefficient of the duct.