Identifying Unknown Samples of Line Pipe

Abstract

Occasionally, a pipeline operator encounters a pipeline or a segment of a pipeline for which the history of manufacturing may be unknown. Aside from the diameter which can be easily measured and the wall thickness which can be determined ultrasonically, how does one go about identifying the grade, the material (iron or steel), the seam type (if any), the manufacturer, and whether or not the material is API line pipe? Some helpful techniques are discussed below. First, it is wise to thoroughly check one's files. Sometimes the mill certificates for old pipe orders still exist. Alternatively, if a third-party inspection company was used, it may be worthwhile contacting that company to see if they still have the mill certificates.

Full scale experimental analysis of stress states in sleeve repairs of gas pipelines

“…Previous work in the ®eld includes evaluations of the strength and integrity of the sleeves by pressurising them to failure, with no attempt to measure the stresses developed during the process [5,6]. Strain gages have been used extensively to monitor stress states in full scale pipeline tests [7,8].…”