LPG pipeline is damaged
LPG pipeline is damaged
(OP)
We are operating a cross country LPG pipeline system. One above ground spurline of 8'' dia & 60 mtr lenght, is corroded at 72 points.Paint is in damaged condition, when we tried to remove paint, it started leaking.We tried in the blowdown line, so the line is isolated.
Spurline is un-piggable. What could be the best and least cost solution to safely
1) Finding the thickness of the Pipeline.
2) Improving the thickness, wherever required
Any other idea also welcomed.
Spurline is un-piggable. What could be the best and least cost solution to safely
1) Finding the thickness of the Pipeline.
2) Improving the thickness, wherever required
Any other idea also welcomed.





RE: LPG pipeline is damaged
So, you have serious corrosion at every 800 mm? Not much hope for that pipeline if you chip off the paint and it leaks. Lay a parallel line and take that one out of service PERMANENTLY, and as quickly as possible.
We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us. Lisa Gansky
RE: LPG pipeline is damaged
Replace it with corrosion protected steel pipe (lined and/or coated. OR, depending on pressure replace with FRP pipe.
RE: LPG pipeline is damaged
Just because pipe lasts a long, long time U/G, it is not immortal. Replacements are required from time to time. This may be your time.
See the SanBruno thread # 378-281116
RE: LPG pipeline is damaged
I believe he said no pigging was possible, as if that mattered.
I urge you guys to reconsider those answers.
We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us. Lisa Gansky
RE: LPG pipeline is damaged
My question is
what is the best NDT method to find the thickness along the pipeline...?
How to improve the thickness, wherever required...?
RE: LPG pipeline is damaged
We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us. Lisa Gansky
RE: LPG pipeline is damaged
If you can't pig it, that's the way I know, except in this case a small wooden hammer might be better. What's your solution?
We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us. Lisa Gansky
RE: LPG pipeline is damaged
RE: LPG pipeline is damaged
60 m of pipe is not very expensive to replace, just replace it, line is blown down anyway. I want to ask about your statement "Improving the the thickness wherever required". How would you improve the thickness? I am curious to know what you are thinking or what they do in your part of the world?
If you need to reactivate before replacement, put temporary sleeves on leaking or thin sections, watch pressure ratings, though I don't know if your code will allow this.
RE: LPG pipeline is damaged
We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us. Lisa Gansky
RE: LPG pipeline is damaged
http://www.clockspring.com/
RE: LPG pipeline is damaged
Cheaper and less labor intensive to just replace the segment. As a bonus, you might be able to sleep better at night knowing that the line integrity has been restored.
RE: LPG pipeline is damaged
Nesamani05 - how would you personally improve wall thickness in these areas? What are your thoughts on how to do this?
RE: LPG pipeline is damaged
We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us. Lisa Gansky
RE: LPG pipeline is damaged
The problem is, without putting the costs on paper, management always wants to mandate "Repair", because is sounds cheaper than "Replacement". You have to show them the costs for:
Multiple repairs, some of which will overstress adjacent areas and cause further repairs.
Weekly inspections of the thin, rapidly corroding sections, to project when this line will go below the minimum thickness required for pressure.
Calculations of pipe stress of the suspended portions, and the minimum thickness required for structural integrety. Pipe may be thick enough to hold pressure, but too thin to spen the distances between its supports.
And the big one; the cost of insurance for the greatly increased risk of a catastrophic leak. If this area, and everything downwind for 100+ meters, is not "Intrinsic Safe" [no sparks, engines, open motors, etc.] that risk includes a Fuel-Air explosion and fire.
Just replace the pipe.
RE: LPG pipeline is damaged
I vote for replacement.
Patricia Lougheed
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RE: LPG pipeline is damaged
Everything had an End-of-Useful-Life. Ignoring it, or using 'bandaids' when major repairs [or replacement] is required has Major consequences.
RE: LPG pipeline is damaged
When one begins to wrestle with the supposed pros and cons of whether to repair or replace a piece of transmission line that has become akin to swiss cheese, you've got to do a gutcheck and just come to the realization that it is not an issue of economics or inconveniences. I cringe whenever I hear the phrase "least costly solution to safely . . . ."
If you are the operator or the inspecting authority, you have nothing less than an obligation to decommission immediately and write it up for replacement if you find that the line can no longer be operated safely and repairs would be an exercise in futility.
This is why people die and pipelines explode because people try to justify and rationalize away good common sense. Not trying to lay a guilt trip or be judgemental, it's just that when you're in a position where you know the truth and possible consequences of a situation, and fail to act in your fullest capacity to rectify the situation, you are responsible.
I hope the pipeline is not in my neighbourhood.
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: LPG pipeline is damaged
How did you determine that the pipe is ONLY "corroded at 72 points"? Were they leakage points? Were they seen throughout the 60 m length? If so the whole pipe should be considered scrap and replaced as others have stated.