While my pipe gently rusts

mayo | environment | news report

Monday February 19, 2007 15:36

by Innealtóir - pipeline inspection team

sorry for Mayo stuff but reckon this is important

This is how the pipeline has coped with a few months of Mayo rain

rust!

READ THIS CAREFULLY

it’s a commentary by Accufacts on the government sponsored Advantica report on the Corib pipeline which appeared in Village magazine…

…..then have a look at these pipeline photos from Friday. Remember that the pipeline has been out in the rain for a few months and then compare to the corrosion estimates above.

Finally think of the pipeline resting permanently in acidic peat bog….

Innealtóir

>>>>>>>>>>>>>>>>
2. Serious Concerns/Questions Still Remain Regarding Internal Corrosion Risks
Corrosion rates can be general or site-specific, usually called selective corrosion. Selective corrosion rates can be much higher than that for the system general corrosion value. As a result, predicted corrosion rates can be substantially different than the actual corrosion experienced on a pipeline. Accufacts is not able to reach any specific conclusion in the Advantica report as to the predicted general corrosion rate, except that these specific studies appear to conclude that inhibitor treatment should prevent excessive internal corrosion. The calculated growth corrosion rate with no corrosion inhibitor mentioned in Appendix D.2.3 of 6.6 mm over 30 years (0.22 mm/yr) appears to be very low for a gas production pipeline. Specific reasons for such a low non-inhibitor value need further clarification (e.g. very dry gas, low temperatures, low CO2 concentration, etc).

Accufacts remains very concerned that internal corrosion may be the predominant risk of concern for this pipeline.

We agree with Advantica's recommendation to re-evaluate the internal corrosion rate prediction, and advise that such prediction methods consider that the onshore production pipeline:
1) has been exposed to the elements for quite some time,
2) may sit in inhibited water for an extended period of time, and
3) will not be periodically pigged with a cleaning pig. All of these factors can significantly increase the likelihood of accelerated selective internal corrosion sites, especially on a gas production pipeline.
>>>>>>>>>