What is the best Subsea Materials Selection Guide or Standard currently available? 3

[Corrtips]

What is the best Subsea Material Selection Guide or Standard currently available?

Thank You.

 

[metengr]

http://www.standard.no/PageFiles/1013/U-001.pdf

 

[Corrtips]

Thank you, Metengr.

Why are some materials acceptable for flowing seawater but not stagnant seawater?

Thank You.

 

[OGMetEngr]

The corrosion rate of many metals depends on the local oxygen concentration at the surface of the material. Low or no flowrates equals a lower oxygen concentration at the surface as compared to a higher flowrate. Stagnant seawater also enables pitting/crevice corrosion of stainless steels, for example, due to the oxygen differential inside the pit/crevice vs outside the pit/crevice.

The tenacity of the protective passive layer of different materials also limits or enables their use in high or low flowrates (e.g. - Cu alloys)

 

[Corrtips]

Thank You.

So in stagnant water the General corrosion rate should be lower because its Oxygen concentration is lower than a higher flow rate condition?

 

[SJones]

The best currently available subsea materials selection guide is EEMUA 194.


194 Guidelines for materials selection and corrosion control for subsea oil and gas production equipment
The new Third Edition of EEMUA Publication 194 reflects the significant developments that have occurred in subsea materials technology and operational experience since the Second Edition was published in 2004. EEMUA Publication 194 is aimed at engineers and others involved in the design, specification, commissioning, operation, maintenance, repair or refurbishment of underwater oil and gas production equipment and related facilities. It provides an overview of the current knowledge of the principles and practices of materials selection and corrosion control for these facilities.
(2012, 3rd Edition)
ISBN 0 85931 188 5

When the water is stagnant, other mechanisms come into play, such as microbially influenced corrosion. Stagnant water also leads to settlement of solids and marine life creating the crevices discussed above.

http://www.nickelinstitute.org/Tech...MarineEnvironmentsNaturalWatersandBrines.aspx

Steve Jones
Corrosion Management Consultant

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

All answers are personal opinions only and are in no way connected with any employer.

 

[Corrtips]

EEMUA Publication 194...is it comprehensive regarding material selection or does it have just a blurb here and there?

 

[TVP]

It is comprehensive. Steve Jones is a subject matter expert in this area, so he is very familiar with the various standards from ISO, NORSOK, DNV, etc.

 

[SJones]

...does it have just a blurb here and there

If you call 148 pages of reasoned discussion with examples, including 8 pages on fasteners and gaskets alone, a blurb here and there, then the answer is yes.

Steve Jones
Corrosion Management Consultant

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

All answers are personal opinions only and are in no way connected with any employer.

 

[MWinczewska]

what about
NACE MR0175/ISO 15156

 

[SJones]

It can be part of the selection process in sour systems, but does not have a subsea-specific approach. It wouldn't be used in H2S-free environments, but subsea materials would still have to be selected in some way.

Steve Jones
Corrosion Management Consultant

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

All answers are personal opinions only and are in no way connected with any employer.

 

[MWinczewska]

so it's EEMUA 194...

 

[SJones]

It looks that way.

Steve Jones
Corrosion Management Consultant

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

All answers are personal opinions only and are in no way connected with any employer.