Onshore and Submarine Pipeline Corrosion Protection 2

[peterwl]

Hello you Rusty Lads and Ladesses (those lovely teapots without spouts),

Im looking for a bit of corner cutting - aint it always the corroded truth!

I would like to read a document on a recently designed corrosion protection system for a submarine pipeline with landfall and onshore pipeline "bits" too - (FEED, Detailed Design or in service would be just "Pitty" and wonderful).

Anything concerning Pipelines and CP would be luverly.

Any ideas - if so do drop a line to:

pwldnvthailand@gmail.com

Thank you and "HIC" !!!

 

[emxhps06]

What's the material of construction?

Will it be a long term protection or short term protection?

 

[peterwl]

Hello emxhps06,
thank you for your response.

It will be carbon steel - exact grade undcertain but possibly API 5L X65 (and possibly with 13 Cr). Possibly 30 inch diam.

What Im really after is the methodology of CP design.

Sub PL probably shell clad Al Anodes.

How to work out the correct "spacings" of the anode shell clamps to ensure good long term CP cover.

What is a rule of thumb - every 1 Km or......?

PL length = approx 300 Kms buried and sub sea

I FULLY appreciate this is a "how long is a piece of string" question - Im looking more for rule of thumb answers AND perhaps calculations?

thank you

 

[SJones]

The usual advice is 'go read the manual', you have several to choose from: DNV-RP-F103, ISO 15589-2 or NACE SP0607. The equations you need, and the methodologies, are defined in these documents, all you have to do is put them together in an acceptable fashion. For the offshore portion, start with the default anode spacing of 300 metres and take it from there. What you do with the onshore section depends on how long it is and where it ends up.

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[peterwl]

MR STEVE JONES,
Thank you Sir - this is a most perfect and helpful answer - excellent.

You have made me feel like that teen son who says to his mother "mum where are my favourite jeans" and his mother replies "have you tried looking in your own wardrobe"

I have the docs you refer to, here, on my desk!!!!!

If you are of a mind, drop me an email (pwldnvthailand@gmail.com), you might be interested?

In the meantime, all the best and thank you so much for taking the time to reply - you are a star Sir.