Platte Pipe Line experienced an operational failure in July 1997. This failure was attributable to operational pressure cycle fatigue crack growth of a hook-crack in the longitudinal seam weld. This defect had grown to failure over a 24-year time period since it had been hydrostatically tested in 1973. In response to this failure, the Department of Transportation (DOT) Office of Pipeline Safety (OPS) issued a corrective order to verify the integrity of this pipeline through either hydrostatic testing or an approved in-line inspection program.
An emerging technology, a Transverse Field Inspection (TFI) tool, was identified as a possible solution to this problem. Even though this inspection tool had not been used previously to identify seam-weld defects, this technology certainly showed promise. The results of our program show that the TFI program resulted in less impact on the operations of this pipeline and provided greater assurance than hydrostatic testing for the long-term operational reliability of this pipeline system. This paper describes the steps required to use this inspection tool for the Platte Pipe Line rehabilitation program.
