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Pipeline repair new technologies......... 2

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dkf

Mechanical
Nov 23, 2001
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Hi everybody!
Curious to see if there is any new technology or method for pipeline repair that is not referred in ASME PCC-2 ?
Any comments will be wlcome.
Thanks
DKF
 
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It would kind of help if you could just summarise / list the technologies /method listed.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Pipe break repair, stress corrosion cracking, coating repair, internal corrosion damage, bad welds, onshore or offshore; what's the specific scope of your question. Being more specific might get you the answer you need.

Technology is stealing American jobs. Stop visas for robots.
 
Little and BigInch

Pipe break, or intrusion in a liquid conducting pipe.
How to stop a static liquid column prior to full empty by gravity.
Yes the question was too generic.
Please excuse.
DKF
 
I'm still none the wiser I'm afraid. You're asking for new technology without saying what is the existing technology. Some better idea of what size, temperature, pressure, fluid, location is required.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Well, let me try
LPG pipelines from 8" to 20" dia some class 600# due to topography.
As for permanent repair there is no doubt.
The question is for the first actions as to stop the leakage and condition for the permanent repair.
We see that freezing is one option, but you have to inject water in the section.
Or has it been made freezing the lpg liquid?
Did anyone develop something like crimping the pipeline, injecting a resin or composite to stop leakage.
Or any other way to stop the leak as soon as you can arrive at the site.
DKF


 
Each pipeline leak may be unique, and the temporary leak repair method can be case by case. In general, the clamp for the straight pipe repair with sealant could be the easiest one to stop the leak.
 
But. "Stop the leakage" does NOT equal "repair the pipeline to safely carry more fluids"

A temporary plug or a temporary patch stuck on the outside of a pipe does not imply that patch is able to carry rated pressures and loads safely underneath the public.
 
Yes, racookpe1978, but our focus is just to be aware that we use the best available procedure/process to perform the "STOP THE LEAKAGE".
After this step, we will permanently repair the pipeline according to rules and procedures in current use.
Thanks for commenting.
DKF
 
The problem with hazardous fluids is that when they are leaking it makes for a hazardous situation. Thus your portions are limited.

If you have a small leak and lots of product you could bolt on a tee and tap the line with a stople or insert a bag and inflate it?

Other than that is a matter of drain down. LPG is worse sure to vaporisation and boiling. Not easy at all.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
To MickMc, we have a local office of Furmanite, but it seems that they provide only the common solutions.
To all:
The question is: what new technologies are being developped for a lpg leaking pipeline emergency repair?
-Is anyone developping something like crimping the pipeline? Wellheads use BOP valves that practically crimp the line!
-Or a safe way to adapt a connection (via robot or other safe mean) to vaporize and vent stack/flare?
-Freeze the pond after a strong water deluge to decrease the hazardous inventory on site? Did anyone try something like this? Is it a reasonable suggestion to perform a test?
Excuse if the whole is senseless.
Already talked to some local experts, but we are stuck......no reasonable ideas were found.
Thanks to all
DKF







 
Widening te scope of the search, I'd like to inform that we are aware of the services provided by TDW, FURMANITE and PLP.
Any other services providers you know of interested in sites bellow the equator?
TIA
DKF
 
Since NatGas and LPG pipelines evacuate relatively quickly and vaporize to atmosphere leaving scarcely a trace, nobody is interested in trying to crimp a broken LPG or NatGas pipeline. By the time the equipment gets out there, it's already departed to upper atmosphere.

What kind of leaks are you trying to stop. You say leaks, yet you talk about crimping a pipeline, which wouldn't be appropriate for anything but line breaks. Well blowouts are kind of another problem. They only have one control point to worry about and put a valve there.

Freezing the pond??? What pond? LPGs vaporize. Robots installing vents. No time for that. Product vaporizes well before you get the robot to site. An installed vent might not be any safer than a natural vent. No ignition source nearby = no worries about ignition, no matter what kind of vent you have.

The best technique to minimize LPG loss found so far is to have closely spaced block valves, perhaps remotely activated? although remote control hasn't been proven to be particularly useful either.

Do you have a problem with the existing clamping solutions, or are you just fishing for new, cheaper or better methods to evaluate? Are they too general for your needs? Do you need a specific solution? Tell us more specifically about what it is exactly that you need to accomplish.

Technology is stealing American jobs. Stop visas for robots.
 
BI, thank you for contribution.
In the last decades I have supported only one leakage that ocurred in one of the by-pass valves of the main SDV in a 24" pipeline transporting up to C5.
When the emergency team arrived the next day and started to dig, the valve was encapsulated in a huge ice block. They had to use waterjet to melt the block, what a mess.
Yes, we had to vent al inventory between the adjacent sdv valves.
I've seen reports that LPG even in small leaks (caused by third part) form an ice block, much smaller than the one above but still, you have to melt it to clear the way.
And yes, we had lpg pipe rupture some 15 years ago. Fortunatelly it was not too far from a terminal and they managed to switch water to the damaged pipeline.
Thank God ruptures are rare events, the norm is small leaks or intrusions.
 
So this is for relatively small leaks that do not quickly self-blowdown the pipeline contents to atmosphere, but tend to freeze plug.

Use as many block valves as you think you need to prevent too much product loss and maintain things to a reasonably safe level.
Put two blowdown valves and vents to atmosphere on each pipeline segment between block valves, one vent valve and vent stack on each side of the block valves.
If you get a leak you can do a controlled blow down without freezing of the segment through the end vents. Shouldn't take too long, if your block valves are not so far apart.


Technology is stealing American jobs. Stop visas for robots.
 
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