Slurry Pipeline Repair
Slurry Pipeline Repair
(OP)
Hello,
Has anybody repaired a slurry pipeline with an external Fibreglass or Carbon fibre wrap? How did they hold up? The slurry is water with some sand in it.
How do carbon fibre/ Fibreglass work in an erosive service? Would they hole through extremely quickly?
Thanks
Has anybody repaired a slurry pipeline with an external Fibreglass or Carbon fibre wrap? How did they hold up? The slurry is water with some sand in it.
How do carbon fibre/ Fibreglass work in an erosive service? Would they hole through extremely quickly?
Thanks





RE: Slurry Pipeline Repair
Assuming the repair is sufficient for pressure, actual erosion rates depend on the abrasiveness of the slurry material, amount of abrasive material, flowrate and impingement velocities against the wall. I might expect better performance, if the repair was only on the top of the pipeline too. If those possible effects are limited, long term repair could be possible, if not , well then, of course.. no.
It would also help if you could be more specific. The term "some" is quite subjective, which I would usually consider would present little cause to worry about without specific knowledge of application. If you said 700 kg/m3 at 10 m/s, I'd worry a whole lot more.
In any case, repair of a steel pipeline with fiberglass material I would not generally assume would be adequate for anything more than a quick fix, very temporary repair, to be "put right" at the first available opportunity, and I do mean "first", not waiting for next scheduled maintenance period, but more like the very next time that a semi-emergency shutdown could be fit into the schedule. The urgency of correcting the repair might be decided based on the monetary amount of damage or loss of sales that might result if such a repair failed again.
"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.live.com
RE: Slurry Pipeline Repair
1. It's a slurry so there's a lot of sand. I don't know the concentrations but if flow velocity decreases the line will quickly sand out (fill up with sand). We pump just above the settling velocity of say 2.5-3.5 m/s. Low pressure - 500 - 1000 kPa.
2. The water recovered from the slurry. There's a very small amount of fine sand but a higher velocity, say 7 m/s and the same pressure of 500-1000 kPa. Could this pipeline be permanently repaired with an external wrap type patch? The damage mechanism we usually see in these pipes is corrosion-erosion, the pipe pits which creates an eddy with higher velocity which leads to self amplifying erosion.
Thanks
RE: Slurry Pipeline Repair
I think you'd likely be able to stop corrosion due to the noncorrosive material used, but at the same time increase the likelyhood of erosion since grp is considerably softer than steel. You have to answer the question of why grp wasn't used to begin with. I would assume it was not used because of its relative softness and shorter lifespana in that kind of environment when compared with steel.
7 m/s is likely to cause erosion with only a relatively very small amount of fines. If you were down at 3 m/s, your chances for successful avoidance would be much better, but you could still see some, probably at changes of direction and at fittings and valves.
"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.live.com
RE: Slurry Pipeline Repair
Any ideas on how a fiberglass wrap or epoxy repair would fare in these two situations? We want to hit our maintenance interval without shutting down...
RE: Slurry Pipeline Repair
Best way is to try it and keep your eye on it on a regular basis to note any early signs of failure.
"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.live.com
RE: Slurry Pipeline Repair
RE: Slurry Pipeline Repair
"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.live.com
RE: Slurry Pipeline Repair
But what's life without a little excitement?
RE: Slurry Pipeline Repair
"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.live.com
RE: Slurry Pipeline Repair
RE: Slurry Pipeline Repair
175 psi
Above ground (40' up) it is supported by pipe shoes and load pads for the section in question
CS A106B
RE: Slurry Pipeline Repair
"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.live.com
RE: Slurry Pipeline Repair
You can even go more than 180 deg and pry it open a little. If it's real thick wall, you can't pry it much though, so you can't get up to like 270 deg arc or anything. Well I guess if you're real slick you could soften it by heating and get it open that way.
You can buy pre-cut patch segments, but we always had pieces of old pipe lying around.
RE: Slurry Pipeline Repair
Frozen waterfalls are very beautiful - we could even chip some ice sculptures for added atmosphere. Then again if it were cold enough it might just steam off. Sometimes colder is better!
RE: Slurry Pipeline Repair
-50 C outside? Might this be an oilsands operation? The presence of any residual bitumen or other oil materials in that slurry would be important info toward understanding the failure, designing a solution and selecting correct materials.
RE: Slurry Pipeline Repair
As to understanding the damage it is very complex due to a couple of changes in our water chemistry. Right now the fluid is pretty clean water with a touch of fine sand.
RE: Slurry Pipeline Repair
yeah . . . think about it. Once you've lost integrity on the ID, it will just keep going through the pipe wall. A wrap type repair is generally intended to shore up the existing material, not completely replace its purpose.
What is your current pipe material?
RE: Slurry Pipeline Repair
"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.live.com
RE: Slurry Pipeline Repair
You've got some fog on your end too eh?
We've actually strayed far from my original question on slurry pipeline repairs - In some locations in our plant a pipe that lasts 3 months is considered old. Where we see velocity increases, direction changes, or turbulence pipes wear out period. I was hoping that somebody would offer some kind of grout/cement repair that is set around the pipe that we could certify (With proper engineering calcs) for our low pressure situation. Our materials perform well for the service, but like anything else when you're talking about a huge quantity of pipe there are going to be some manufacturing defects which lead faster erosion....
RE: Slurry Pipeline Repair
As mentioned we also have neoprene lined pipe as well. Mainly CCO though.
RE: Slurry Pipeline Repair
Did you see my comment on polyethylene pipe? Of course, that's based on the assumption that you're wearing thin on the bottom and only need a partial wrap. Well, I forgot about the -50C, maybe that rules it out.
If you need complete wrap and can use PE, you could afix 2 half rounds that are pre-mitered and then weld them together. If you can't match the ID, make up the gap with neoprene sheet. Heck, you could just use neoprene (or other such elastomer) sheet backed with thin bendable steel and strapped on.