Abstract: Utility lines or cables are installed in underground conduit using imperforate flexible tubing having a circumference no less than that of the conduit interior. One end of the tubing is everted and fixed within the conduit near end. Air blown into said near end is directed against a displaceable pocket between the fixed everted end and entering portion of the tubing so that the tubing lines the conduit interior wall, taking its shape and strength therefrom, as it is advanced through the conduit to the far end thereof. In one embodiment, the tubing when half way through is severed outside the conduit near end and a pull line attached thereto is drawn with the tubing the rest of the way through the conduit to its far end; and the tubing is twisted on the pull line to form a tow of higher tensile strength.

Abstract: A dispensing device is pulled through a conduit while a coating material, such as a lubricant, is forcibly dispensed from the dispensing device and spread along the interior surface of the conduit. The dispensing device has an elongate tubular body with a hollow interior portion adapted for containing a supply of the coating material and having an opening in the body through which the coating material is dispensed. An elongate connector extends axially into the hollow interior of the elongate body through the leading end thereof and is connected to a piston located inside the hollow body. When the dispensing device encounters a frictional resistance as it is pulled through the conduit, the piston is pulled forwardly in the hollow body to forcibly dispense coating material from the dispenser and the dispenser thereafter spreads the coating material along the wall of the conduit.

Abstract: Cable pull lines are pneumatically rodded through underground cable housing conduit comprising joined multipassage sections by attaching the free end of the pull lines to individual foam carriers inserted into each passage at one end of the conduit and forcing air through a manifold into said passages behind the foam carriers to simultaneously drive the carriers to the open exit end of the conduit. The pull lines have been previously uniformly wound on a reel and a brake is used to tension the reel as the pull lines unwind therefrom to keep the foam carriers in phase as they advance through the conduit and thereby to prevent air bypassing the leading foam carriers through gaps at the conduit section joints with resultant loss of driving pressure.