In-Line Tools

There are three types of metal loss tool: magnetic flux leakage (MFL), ultrasonic and eddy current.  MFL includes both axial and transverse fields tools.  Eddy current tools have very limited application and very few tools are available.

The accuracy of measurement of individual tools varies massively.  In certain cases the accuracy is very shape dependent so that a tool may determine the size and shape of one area of metal-loss very accurately whereas in another area the accuracy can be very poor.

Metal loss detection is significantly affected by pipeline geometry and conditions, especially gas lines where severe velocity excursions can be experienced at low pressure or low velocity.

We assess pipelines and review inspection contractors' proposals to ensure that pipeline operator's expectations are achieved.

There is no independent validation of the performance of inspection tools.  The performance provided by alternative contractors with individual tools may vary markedly.

We have the expertise to examine the quality systems of inspection contractors, their past records and their data to give an independent assessment of their performance.

In certain circumstances it may be necessary to determine whether a particular tool can detect unusual metal-loss features such as weld defects or worm holes.

We undertake independent pull-through or loop trials to assess the performance of a tool.

Many other in-line tools are available for various purposes such as mapping, geometry, crack detection etc.

We have experience in the use and limitations of most of these tools and give advice accordingly.