Leakproof Pipeline 5

[dik]

Is it possible to construct a pipeline that is reasonably leakproof. Does it have to be exposed, buried, or whatever? The actual construction? materials? single or double wall? monitors for leakage? inspection both during construction and in service? cost? any other issues?


Dik

 

[mk3223]

Sorry, not so sure what are the questions.
Everything is possible....

 

[3DDave]

You've posted a lot. What brings this question?

 

[dik]

3DDave:

Just wondering if it is possible to construct a leak proof pipeline and what the issues are.

Dik

 

[europipe]

As designers we do our best.
As less flanges as possible is one of the issues.

 

[BigInch]

Interesting question.

The answer is both yes and no.
Yes, IMO, and practically speaking, you can build a leakproof pipeline.

The second question is, "Is it practical?"
No, IMO, , leaving economic practicality aside, if it is practical, it will only be practical for a limited time. Design life and maintenance costs will eventually catch up to practicality of operating it any longer. As has been proven an number of times lately, it is not likely to catch up to corporate greed. Operating life will be extended past design life to the point where maintenance failure overtakes utility.

Third question is, "Is it practical to be operated as a leakproof pipeline?" I think this is the most problematic. If it is practical to build and operate for a limited time, you've got a few other factors to consider as well. Statistically there are three most consequential and very important causes of leaks. If you were always able to maintain complete control of these variables, it might be possible, but the practicality of what that means is, I don't think so. At least not all the time.

Factors
1.) External Corrosion
2.) Instrument and Control Errors (control may involve human factors)
3.) Third Party Damage
4.) Costs of monitoring and correccting all the above, before a leak occurs.

Mitigations
1.) External corrosion difficult to see on a buried pipeline and expensive to repair, if you do manage to locate it in time.
High cost to examine. Errors in prediction of remaining life.
Not buried would subject the pipeline to other more dangerous factors, coating damage? Vandalism .... bullets?, socio-environmental unacceptability, PROPERTY VALUE EFFECTS, etc. Would you really want an above ground pipeline in your neighborhood? Not me, "leakproof" or not. Leak detection... like terorist cameras... are too late to do me any good.

2.) Increased use of instrument and controls is increasingly subject to errors.
Will new technology and increased use improve control, or degrade integrity due to hacking and instrument failures. Accidential overpressures. Human control room response errors. Level and relief valve pressure controls failing more. More complex, expensive, error-prone maintenance.

3.) Third party damage is causing the most loss of life and property damage. There is little control of the situation now. There is a very high cost of protection from this factor. Lots of farmers and road repair crews and sewer installers out there. Offshore, protecting for an anchor dropped in the wrong place and you might be burying 18 ft or more everywhere?

4.) Other factors. How long a pipeline and location. Some things might be far more practical for a short pipeline of 1-10 km, but not practical at all for 1000 km of onshore or offshore.

I add
5.) Regional security. Leakproof and terrorist activities aren't exactly compatible under any circumstances. All PRACTICAL terrorist defences of pipelines of normal length effectively say that protecting pipelines from terrorist, or extreme vandalism is impossible from a practical standpoint. It is recognised that high cost of military patrols necessary to prevent leaks and response times allow effective protection only at high profile nodes of delivery hubs, terminals. Pump stations may or may not be included. Protecting every km of pipeline joint and emergency valve stations along the root 24/7 just is not practical.

So, consider those factors and the cost of mitigations and I think you might be able to get away without leaks for a relatively short time. The answer is probably, "Yes. Theoretically you can build a leakproof pipeline, but the practicality of the situation is, NO, or, Only for a limited time.

There's probably more I'll think of later.

Technology is stealing American jobs. Stop visas for robots.

 

[LittleInch]

What is "reasonably leak proof" compared to "standard" pipeline design?

The most leak proof pipeline I've ever seen was a 12" high pressure ( 70 bar) gas pipeline which ran 3km along a beach front road where hundreds if not thousands of people could be present on a nice summers day.

This line was buried with 2 to 2.5m cover (extra depth is good for risk reduction), had a coloured red concrete slab on top projecting out beyond what a digger could reach, was 19.1mm thick ( much more than required for pressure containment), had a fibre optic cable above that so that any digging which breached it alarmed with a location. That was 20 years ago and now you would make that FO cable act as an intruder / third party pro active detection system. Every weld was x rayed and the whole thing hydrotested to a high level (105% SMYS). Standard 3LPP coating and cathodic protection system.

The pipeline could be internally inspected so any external corrosion ( it was dry sales gas so no internal corrosion) could be monitored on a 3-5 year basis.

The only extra thing they could have done was make it a true pipe in pipe double containment where inner pipe failure wouldn't escape and also the outer pipe would act as extra protection, but I think that was seen as really going too far.

Cost was about 3-5 times "normal" pipeline length but the alternatives were even more costly as involved complex drills and a longer length.
Now that's about as "leak proof" as you can "reasonably" get IMHO.

Otherwise BI has the basics nailed - yes feasible especially for short small diameter lines, large long distance lines - not economic.


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

 

[dik]

Big and Little Inches:

Great replies, in particular Big Inch, a lot of effort went into both replies.

My son asked me if it was possible to design a pipeline that was leakproof... and, I couldn't give him an answer. I knew it was possible to construct one that was nearly leakproof, and, that as more effort went into it (and cost) the chances of it leaking were diminished. I didn't know if buried, or exposed was better and I didn't know what construction would be involved for the actual piping. I thought properly welded would be better than bolted, but, wasn't sure. Part of the issue, I guess, is assigning a maximum life expectancy with necessary inspections. I don't know how they are inspected. For small pipes, a small robot going down the pipe, X-raying welds?

again, thanks Dik

 

[LittleInch]

Yup,

buried better than above ground
deeper you bury it the better
Welded better than flanged,
Thicker better than thinner
extra things in the way to stop someone digging it up
Sensors / cables to detect someone digging

All cost more than normal.

Internal inspection is intelligent pigs - look them up
One of these bad boys

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

 

[dik]

FYI:

https://www.nace.org/uploadedFiles/Committees/SP010210.pdf

Pretty good file on inspections...

Dik

 

[TenPenny]

All of the 'pipelines' in the wall of my house are leakproof, so I guess the answer is 'yes, it is possible'.

 

[dik]

TenPenny... maybe just a matter of time. I'm thinking of pipelines that carry materials that could be damaging to the environment in the event of a leak. My son was asking about a pipeline for oil products from Alberta to the Pacific Ocean.

Dik

 

[BigInch]

Surprisingly enough operating at higher pressures doesn't have all that much to do with either explosions, property damage or death count... according to the statistics. Pipeline stopping leaks rarely happen near or above maximum allowed operating pressures (MAOP). Probably because most of the length of a typical pipeline does not operate at MAOP anyway. That means there will naturally be more exposure to damage from both third party activity and corrosion in the relatively longer lengths regions where lower pressures prevail.

Technology is stealing American jobs. Stop visas for robots.

 

[IRstuff]

While BI and LI touched upon it, the biggest issue with leakproofing is not an engineering problem, per se; it's an economics problem. Whatever the cost adder you wish to imagine for the pipe that you want to call "leakproof," what is the penalty for having a leak, and how long does it take for your investment (the added cost) to break even. These questions are engineering related, in a sense, as every engineering decision tends to shaped by the economics and deepness of pocketbooks. Ford did that analysis for the Pinto, and decided that the risks were sufficiently low enough to justify not adding a bracket that would have prevented loss of life during a particular type of rear-end collision:

https://philosophia.uncg.edu/phi361...oes-business-need-ethics/case-the-ford-pinto/

While pipes might not necessarily rise to the level of loss of life upon a leak, there certainly are cost factors in environmental cleanup, etc., coupled with the rarity of such occurrences, given proper and adequate maintenance and testing. So, when the pipe is a tiny part of an overall, large, cost, such that a 2x or 3x pipe cost is inconsequential, then it's likely someone could decide to make that pipe.

However, in the majority of the cases, there will more likely be cries of "gold-plated pipes," and, "when are we getting our investment back," than any concern about an infrequent, and usually, low-cost, event. While we don't like to think about the life and death costs of everything we do, buy, or use, they are there, buried on some spreadsheet, in some archive. The bottom line is that we cannot afford to make everything literally bulletproof, so we live with those risks, even though the average Joe is completely unaware of the risks and costs thereof that someone has assigned to him.

We treat risks asymmetrically, and disproportionately, anyway. We're more concerned about terrorist attacks in the US, even though they've killed fewer people in the 16 years since 9/11 than the death toll from 2 months of traffic fatalities. We willingly and blindly ignore the risks of dying in our cars, even when presented the data, over and over. People continue to text while driving, even on the freeway, despite repeated warnings. Do we or should we allow Darwin to deal with those people?

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[dik]

I gather that with proper planning and design, for additional costs, pipelines can be made much safer. It's a matter of determining where the balance is. Have there been any studies done on this? I cannot think of the term, but, there were studies done in economics when I went to university using linear programming to determine items that may have been similar.

Dik

 

[MikeHalloran]

I gather that with proper planning and design, for additional costs, pipelines can be made much safer.

Not a totally supportable assertion IMHO.

Google "Hanford" for examples of what an unlimited budget cannot do.


Mike Halloran
Pembroke Pines, FL, USA

 

[dik]

Thanks MIke... anything to add that could improve the safety?

Dik

 

[IRstuff]

I would bet dollars to donuts that anything cheap that could be done has already been done. Clearly, there is some need to appease public opinion, so low-hanging fruit have already been gathered so that the pipeline companies can use them as examples of their proactiveness in pipeline safety.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

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[dik]

Have enough constraints to set up a linear programming model for my TI Nxpire calculator that can do the linear plots w/fill... Had nothing better to do this evening... forgot a 'whole bunch' about linear programming, but, it's like 'riding a bike'.

Dik

 

[BigInch]

No LP required IMO. It is well known in the industry that corrosion is by far the #1 cause of all leaks and third party activities cause the most property damage and loss of life.

1.) Pipelines are already installing the components necessary to use the inspection pigs LI pictured above in all new regulated pipelines and over the next 20 years or so for old pipelines.

2.) There are One Call programs operating in every state that contractors should call before digging. More could always be done to educate contractors, as that is critical and ... a never ending battle.

3.) A regulation requiring excess flow shutoff valves is being contemplated, but they won't activate until after a break or leak occurs.

4.) A new federal regulation to extend regulatory authority to include a number of rural and some other pipelines that have not been previously regulated is being contemplated. Pipeline companies and trade lobbyist organizations have commented during the regulatory process that they are against this provision. That is not surprising, especially given the current political climate. Yet they were not anywhere to be seen when this Plains All American Pipeline Co pipeline leaked 140,000 gal. That pipeline is offshore, yet in state waters and apparently not included within the federal regulatory program, falling into a regulatory black hole between federal and state waters. Recently sold between two companies, neither one apparently knowing what its operational state was at the time and eventually finding out the hard way that it was actually pretty damn poor.
2015 California offshore pipeline leak

I think that public opinion is so bad at the moment that, no matter what the cost, certain things will have to change. Frankly most pipeline companies are great money makers and can afford to play the game no matter what the house rules are, so drain the swamp, build some safe pipelines and pump out what's left.

What I would like to know...
Is it my imagination, or does the rest of the world's pipelines appear to be safer. Is it that the USA simply has so many more pipelines? I don't think for the most part there is any essential differences in design. Codes are the same ASME as the US, nearly exact copies, or very similar. So, for example, are European pipelines constructed better? Operated better? Inspected better? Maintained better. All the above, or is it just my imagination.

Technology is stealing American jobs. Stop visas for robots.