Patent ID: 6180169
Filing Date: 2001-01-30
Classification: F16L

Abstract:
A method for internally coating a joint or other discontinuity in a live gas pipeline, comprising the steps of:(a) attaching an insertion duct to the pipeline;(b) inserting a coating unit through the insertion duct into the pipeline, said coating unit having a spraying mechanism;(c) orienting said coating unit in said pipeline adjacent to the joint or other discontinuity to be coated using a flexible conduit operatively attached to the coating unit, said conduit being sufficiently rigid to propel said coating unit and said conduit being sufficiently flexible to maneuver around bends or other obstacles in said pipeline;(d) pumping a coating material to said spraying mechanism; and(e) spraying the interior of said pipeline at a desired location with said coating material, wherein the coating material is applied to the interior of the pipeline in the presence of a pressurized gas and wherein the coating material is capable of sealing the joint or other discontinuity regardless of the presence of filler material.