Does TranScan replace hydrotest?
Yes. TranScan identifies seamweld features in the pipeline without making them worse. Hydrotest can grow a feature during the test, which can subsequently fail within months of the test. One pipeline operator did more than 2,000 excavations following TranScan runs. Many of these defects were cut-out from the line. Some were burst tested. These burst tests identified one joint that burst at 105 percent of the hydrotest pressure and many more that burst at higher pressures. This shows that TranScan can identify features for cutout or repair far in advance of hydrotest. In-service failure of features is therefore less likely, and the pipeline does not have to be taken out of service (with revenue losses) to find those features. The first two sections of the pipeline system above were hydrotested after TranScan inspection, report and repair. They passed at 1.25 MAOP. Thereafter, the DOT regulator accepted TranScan inspection and repair as an alternative to hydrotest for the hook crack prob
