Page 327 - Pipeline Pigging Technology

Pipeline Pigging Technology

Fig.4. Schematic example of assessment of OH reported defects.

In effect a 'weak-link' approach is necessary. This approach works on the
principle that any failure in a pipeline is unacceptable. Therefore, only the
worst area of corrosion, in a pipeline of any length, need be assessed to
determine the integrity and future operation of the pipeline. When dealing
with bulk data analysis from repeat runs, it is unlikely that a single area of
corrosion with a single corrosion rate in a single spool will emerge as the most
severe. Instead, it is likely that a group of spools will emerge as the most
severe.

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