Steve, no conclusions yet. This could turn into a lab work.
Regarding your comment "As for using 9Ni with 625 cladding subsea, good luck with that. It does not feature in any subsea materials selection menu", What do you think if it were low alloy steel with 3.5% Ni and 625 clad? This fits the...
Steve,
I am not sure if I understand the difference between the minimum metal temperature and the minimum design metal temperature. The client has only one "minimum design temperature" which may only be seen during start-up due to Joule–Thomson effect.
Thank you for the replies
Lee, to answer yor comments
1- Alloy 625 will be used as the clad material for internal corrosion protection. the proposed base material is a low-carbon nickel alloy steel with nominal composition of 9Ni, which is particularly used for low-temperature or cryogenic...
Hi All,
We have a subsea well tie-in spool with minimum design temperature of -85degC (although the duration at these temperatures will be very short). The material has to be corrosion resistant such as 316L. However the required wall thickness of 316L material for pressure containment makes it...
Well, this will be a very general statement but all depends on what your internal and external conditions are. Is it dry gas inside and at atmospheric conditions outside? Or is it highly corrosive fluid line subsea? What are the operating conditions etc? What is the material you are using?
As...
Hi Everyone,
I am planning to apply for NACE Corrosion Specialist exam but don't have a clue about its format. Does anyone know whether it is an interview, problem solving/designing assay or just multiple choice questions?
Thanks.
Hi Steve,
thanks for the answer. my concern is coating disbondment for wet insulation systems. I am trying to understand whether CP works or shielding comes into play. as I understand seabed sediments may be deaerated but then how temperature effect corrosion if CP is shielded. or is there no...
Hi,
I am looking for information on Corrosion under insulation for subsea pipelines with cathodic protection. almost all the references I found are mentioning CUI of piping in above ground installations.
specifically, I am looking for some answers to the following subjects. For subsea use...
Hi,
we want to order new 316L SS tubes based on ASTM A269. However, we have been made aware that small diameter tubes may have suffered internal contamination and pitting due to manufacturing process resulting from insufficient cleaning (especially for small dia tubes) and this is accepted...
thank you for the Answers.
So we don't try to calculate the pitting rates in design stage to increase the calculated Corrosion allowance but we rely on maintenance strategy. Inspection results will give the actual risk of pitting and the required strategy.
Hello everyone,
I am new in this forum and hoping to get some help for the following.
I am checking a pipeline corrosion assessment study as part of my training. the pipeline is for a multiphase oil production line including 120ppm H2S and 3% CO2. I understand that the primary corrosion is due...
