Abstract: A method of detecting inadequately supported sections or overloaded points in a pipeline including the steps of traversing the interior of the pipeline with an instrumentation pig, sequentially striking or vibrating the wall of the pipeline by means carried by the pig to introduce vibratory signals into the pipeline, receiving said signals from within the pipeline by listening to the sounds generated as a consequence of the striking of the interior wall, and detecting preselected characteristics of received sound which are indicative of unsupported sections or of points of load and stress concentration in the pipeline.

Abstract: A branch fitting for providing access to the interior of a pipe, the fitting having first and second body portions each having a semi-cylindrical surface adapted to sealably engage the pipe, the body portions being secured together and to the pipe in a pressure retaining relationship, one body portion having a first and second integral cylindrical barrel portion extending in the plane of the tubular axis of the pipe, the cylindrical axii of the barrel portions intersecting each other at a point at or adjacent the pipe wall, a cutter within one of the barrel portions having a shaft extending sealably exteriorly of the barrel portion whereby the cutter may be rotated and axially advanced to form an opening in the pipe, the opening being coincident with the cylindrical axis of the second barrel portion. The second barrel portion may contain a plugging member and means of delivering it into the interior of the pipe through the formed opening.

Abstract: A pipeline pig is provided which is especially adapted for use in conjunction with laying offshore pipelines in that it detects and indicates dents, and other disconformities in the nominal cross-sectional configuration of the pipeline which may occur as a result of the laying of the pipeline. It employs a plurality of prolate spheroid rollers arranged to secure substantially full circle coverage of the pipeline and yet only a minor portion of the length of the rollers will be normally in contact with the pipeline thereby reducing the wear on the remaining portions of the rollers and increasing the ease with which the pig can be towed along the pipeline. In another aspect, a system is provided in which a pig includes with a means of sensing a condition along the pipeline and a memory means for storing the output of the detecting means.