Abstract: There is provided herein an electrical robotic system for locating, cleaning, and repairing holidays within coated pipe that are proximate to a girth weld. In a preferred arrangement, a robotic train will be placed in the pipeline that will perform the functions of holiday location, cleaning/preparation of the surface containing the holiday, and repair thereof, in a single run through the pipeline.

Abstract: There is provided herein a robot-based electrical system for locating holidays within coated pipe that does not utilize a grounding wire. In a preferred arrangement, the robot will carry a metal rotating brush/capacitive pad combination and changes in the capacitance in the brush/pad circuit will be used to identify imperfections in the interior coating of the pipe and especially those located proximate a girth weld. In another preferred embodiment, a circumferential brush will be used that allows testing of the integrity of the internal coating throughout the length of the pipe as the robot travels the pipeline.

Abstract: There is provided herein a robot-based electrical system for locating holidays within coated pipe that does not utilize a grounding wire. In a preferred arrangement, the robot will carry a metal rotating brush/capacitive pad combination and changes in the capacitance in the brush/pad circuit will be used to identify imperfections in the interior coating of the pipe and especially those located proximate a girth weld. In another preferred embodiment, a circumferential brush will be used that allows testing of the integrity of the internal coating throughout the length of the pipe as the robot travels the pipeline.

Abstract: An inspection robot is provided to traverse the interior of a pipeline for the purpose of checking the coating at the interior surface of the pipeline at the weld seams. The robot is designed to determine the thickness of the coatings and to provide a visual and recordable reading thereof. The robot is provided with a holiday detector in the form of a conductive brush mounted on a rotatable hub and adapted to sweep against the weld seam so as to locate any voids in the coating by means of electrical conductance, thus causing a holiday marker to activate and mark the pipeline interior surface so that the site can be revisited for repair.