Nexen Pipeline Failure
Nexen Pipeline Failure
(OP)
Have a look at the attached (Heat-Traced Pipelines – A Double-Containment Solution for a High-Temperature Pipeline). This is an article from the 2014 IPC event in Calgary. I kept it because at the time I was very interested in alternative design solutions for hot bitumen pipelines.
I dug it back up last week when I heard the news of the Nexen double-walled emulsion line failure at the Long Lake SAGD facility. In the article, they do not name “the operator, a major Canadian Oil & Gas company” but from what I know of the Nexen facility, the details seem to describe the recently completed Long Lake buried produced emulsion pipeline project. As more details of today’s unfortunate spill are disclosed, I believe there is a strong chance that we will discover that the failed Nexen pipeline is in fact the NPS 16 emulsion line described in the attached IPC article (although at this point it’s pure speculation on my part).
Interesting read in any case. Especially since the main sales pitch for pipe-in-pipe technology is that it can achieve extremely sensitive real time pipeline integrity surveillance (i.e. “leak before spill detection capability, second-to-none leak detection sensitivity (x1000 relative to volumetric methods”).
Follow-up to above
See link below:
http://worldheavyoilcongress.com/sessions/construc...
I dug it back up last week when I heard the news of the Nexen double-walled emulsion line failure at the Long Lake SAGD facility. In the article, they do not name “the operator, a major Canadian Oil & Gas company” but from what I know of the Nexen facility, the details seem to describe the recently completed Long Lake buried produced emulsion pipeline project. As more details of today’s unfortunate spill are disclosed, I believe there is a strong chance that we will discover that the failed Nexen pipeline is in fact the NPS 16 emulsion line described in the attached IPC article (although at this point it’s pure speculation on my part).
Interesting read in any case. Especially since the main sales pitch for pipe-in-pipe technology is that it can achieve extremely sensitive real time pipeline integrity surveillance (i.e. “leak before spill detection capability, second-to-none leak detection sensitivity (x1000 relative to volumetric methods”).
Follow-up to above
See link below:
http://worldheavyoilcongress.com/sessions/construc...





RE: Nexen Pipeline Failure
RE: Nexen Pipeline Failure
PIP is far too labor intensive and costly for my tastes anyway.
RE: Nexen Pipeline Failure
The thing I've never liked about this PIP system is the vacuum you need to pull on the annulus to get the insulation to work effectively. Monitoring this annulus pressure then becomes your leak detection system either from the inner pipe or the outer pipe. however any exterior or interior leak destroys the vacuum and the insulation properties.
Its not clear to me though what happens if you get a small or big leak in the inner pipe which then heats up the outer pipe in a small area. The outer pipe is not normally a pressure containing pipe, but as thin as you can make it to reduce costs. Thus it could easily fail under thermal stress.
A "fish mouth" failure implies local buckling and overstress to me.
Given the contents are a mixture of oil, water /steam and sand, the potential for erosion or even under sand corrosion seem quite high.
Will be good to read the report when it finally comes out in about 18 months time.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Nexen Pipeline Failure
Piping Design Central
RE: Nexen Pipeline Failure
The inevitable thermal cycling of the entire system could have broken something within..... the support scheme might not be functioning as designed...... There is no way to tell.
I also wonder about the design pressure/temperature rating for the exterior pipe. Shouldn't it be the same as the interior pipe ? What was the actual pressure test of the exterior pipe ?
The claim in the above link: "....provides a mechanically sound support for anchoring the inner pipe and thus allowing the installation of the high-temperature pipeline in non-competent soils with no expansion loops and no external anchors" bothers me...
I sense the smell of an MBA ...... with a strong concentration in sales and marketing
MJCronin
Sr. Process Engineer
RE: Nexen Pipeline Failure
Remember this is a pipe with contents of 100c plus which would cool down rapidly if you didn't have very good insulation.
They do often run FO cable inside to check on temperature, but you might not see a big difference and its really there
MJC The outer pipe is often not a full pressure design to reduce costs as any internal leak is not supposed to gather. If the insulation gets wet its ruined so you can't hydro test the outer pipe and the inner pipe could collapse.
Mechanically it does the john normally but does impose stresses on the outer pipe to purees stress the inner pipe which might not have been assessed as well as it might.... Who knows, perhaps the outer pipe failed some time ago. I will be very interested to see the results of the investigation if they ever see the light of day.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Nexen Pipeline Failure
All this is not "official" but comes from a very good source.
If this is correct, it sounds like it will be "operator error" rather than design failure.
Any one seen anything released officially??
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Nexen Pipeline Failure