CRA-clad and CRA-lined Pipeline Failures 3

More importantly, do you actually know of any in service?

CRA lined and clad is occasionally used for manifolds, short flowlines, but I'm not sure I've heard of any significant lengths.
CRA clad and CRA lined are usually just used as a comparison to do something else, like use Duplex or Super Duplex or C Steel with a bunch of inhibitor

Either way, with the very small km and their inherent reduced corrosion, together with pipelines very low "failure" rate I'm not sure you're going to find any data worth having.

Also define "failure".

Corrosion defect?
pin hole leak?
Small hole?
Full bore rupture?

As with a lot of this, the knowledge stays within an operating company and they are often very "tight" about releasing failure data.

Any reason for your question?

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Hello,

Thanks for your response.

There certainly are thousands of kilometres of CRA-clad and CRA-lined pipelines currently being operated.
Apologies if my question wasn't very detailed, however the information will help with some research I am completing at the moment.

A paper with some examples is, "Experience with Lined and Clad pipelines", by Asle Venås and Jens P. Tronska.

Good point about "failure". Perhaps in this instance, it could be suggested to be any significant flaw or threat that is impacting the integrity management of the pipeline. So all of the above.

And you're certainly right, the information is likely not to be in the public domain. But it is worth the question.

I have seen a few papers at NACE on the subject.
Everyone that I can recall was related to welds.
I was much more interested in clad failures in high temperature systems.

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P.E. Metallurgy, consulting work welcomed

"There certainly are thousands of kilometres of CRA-clad and CRA-lined pipelines currently being operated."

Care to name any or any areas?

And thousands in the hundreds or thousands of thousands of pipelines is a very small percent.

See e.g.
Maybe contact them?

Or join this JIP
They are all pretty much high end, high spec systems. As such they tend to be hot high pressure lines and failures are usually a result of a miscalculation or operating conditions being different to reality, e.g. the number of start stops designed for is less than reality.

Most internally clad systems I've even seen ignore the cladding in the WT and strength analysis areas as it is just too difficult to get the analysis to work and basically not worth the effort for what 3mm of clad or liner gives you. So they should be stronger than most other flowlines.

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In ASME B&PV work you have to ignore the clad for strength calculations

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P.E. Metallurgy, consulting work welcomed

Sarawak Shell Berhad lost a 316L clad pipeline after seawater ingress during wet parking before commissioning (it may have been the Jintan pipeline, but my Shell memory is hazy). It was this loss that elicited their work on safe exposure periods of CRAs for the South China Sea. The replacement pipeline was upgraded to 825-clad.

@LittleInch - Kashagan was a big customer of clad pipe to replace the carbon steel pipelines that cracked in the high H2S service. Took the world’s supply for a year.

Steve Jones
Corrosion Management Consultant


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

Steve, fair enough. I avoided the disaster zone that was that development. But it kind of proves the point that these lines are basically flow lines used for horrible fluids which are high risk. So there will be some failures especially as the construction is not common and complex welding.

I'm not sure what the OP is really after, but if you and Ed don't know then not many others will...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

@EdStainless, thanks for your response. NACE does have some excellent papers.

@SJones, thank you. Yes the Jintan pipeline is definitely the most "famous" CRA-clad pipeline failure. My understanding is that it was a leaking valve on the temporary pig laucnher which was responsible. There are some incredible photos of the girth weld pitting that resulted!

@LittleInch, thanks again. You seem very defensive about things, and I'm unsure why? It was never in question that CRA-clad and lined pipelines would be selected for harsh service conditions, that is obviously the point of the materials. The POF-510 guideline is a useful one, and I had not come across the TWI JIP, thanks for passing that on. There is some interesting efforts underway to ensure the "triple-point" of MLPs can be successfully inspected, as this interface has been a point of failure for a Brazilian pipeline from what I've been told.

The purpose of the question was to encourage answers like that from SJones. If the community knows of any CRA-clad or CRA-lined pipeline failures/issues, it would be very useful for a research project I'm currently working on.

Thanks everyone.

@subsea

You seem to know more than us already. Yes, the triple point has been the source of some “issues” recently in Brazil for Technip. Another factor with the triple point in H2S service is that it will not be compliant with ISO 15156 thus requiring qualification corrosion testing.

Steve Jones
Corrosion Management Consultant


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

Subsea,

I don't intend to come across as defensive, but I guess I'm just not sure where you're coming from.

The initial question was rather short and vague and it usually works better here if you let people know a bit more of your back ground, where you've already looked and who you've contacted and what the purpose of the research is. Is it for a thesis or some particular study?

The actual pipe material has a generally good reputation I believe, but welding, installation and operation are where things have a tendency to go wrong, but often very difficult to get hard information from operators.

My other point is that the km of clad pipe is still quite low compared to other types of pipe so its difficult to extrapolate any "failure" data as one or two incidents will create a blip in the data and no failures reported doesn't mean the risk is zero.

I had to look up your ref and found this?


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@LI
I think that it's more this:
Same company though.

Steve Jones
Corrosion Management Consultant


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

Goes into a paywall, but I get the drift....

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Has anybody ever had a trouble free CRA?

Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

I know of some chemical plant installations that have worked fine for >10 years.
The weld procedures are super critical and easy to get wrong.

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P.E. Metallurgy, consulting work welcomed

The CRAs are trouble free, it’s the people dealing with them that aren’t

Steve Jones
Corrosion Management Consultant


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

I've wondered before about the unholy mix of metals in the weld with clad pipe, C stl and the filler rod all mixing together in or close to the root.

Do they do the root weld as TIG or something similar? Then switch to some thing else for the remainder?

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Generally, the bevel design will result in interaction with the carbon steel only in the second pass. Pulsed TIG would probably be ideal, but too slow. Pulsed MIG all the way through appears to be the most adopted process. The real issue with mixed metal comes with the use of a zone of weld overlay at the ends of lined pipe (MLP) to assist with NDT, and to facilitate repreparation after a cut out.

Steve Jones
Corrosion Management Consultant


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

I was recently offshore for a reeled CRA-clad pipeline installation. The welding process was only manual GTAW. I was reading something interesting about how inconel weld consumables are preferred over duplex now because of the thin layer of martensite they cause in the CS HAZ and respective lowered joint toughness.

But you're right @SJones, the issues are only after the root pass and in the over-matched weld between the CS and consumable. This is reflected in the ECA requirements only requiring consideratoin of flaws in the weld/HAZ area above the clad/liner.