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Reuse Jack and Bore Casing Pipe? 1

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CivilSteve

Civil/Environmental
Aug 24, 2022
3
Hello,

I have a project I am helping with and I was just wondering if anyone has every re-used a casing pipe or carrier pipe in a project before? We need to make sure that the casing pipe can be re-used and we can just pull out the carrier pipe. Typically, out here in the southwest the casing pipe is filled with sand once the carrier pipe is in place. Is there an easy way to get the pipe out of the sand or another method that doesn't involve sand?

Thanks in advance to all your time and help!
 
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What the H are you talking about?

Casing pipe of a water well, gas or oil? Carrier pipe for what? Why do you need a casing? Road crossing? Culvert? Pipeline? Electric cables?


Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
 
It is for culinary water and sewer pipe going beneath a road and railroad.
 
Since oil and gas pipelines casings are not filled with sand, Sometimes paraffin, sometimes nothing.
Sand; I don't know. Can you wash the sand out then pull the pipe? Plus normally we would not be removing and reusing something that is still good; we'd probably be building a parallel line with a plan to operate both together.

We would probably not reuse carrier pipe, although it's probably been done occasionally. We have rather strict requirements and pulling it for reuse would most likely cost more one way or another.

Casing pipe might be reused, depending on condition. No strict requirements for us there. Again, probably costs more to remove and reuse than buying a new one.

Hard to imagine a railroad actually letting you pull a casing out from under them.

Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
 
How long is the crossing / casing pipe?

I think anything more than 25 to 30m will be very difficult to remove the carrier pipe.

Now what state the carrier pipe is will be the issue and how you can even find out before you spend all the time and effort to remove the carrier pipe.

Normally I would have thought you would internally line the carrier pipe or use that as the "casing" and install a smaller pipe within it.

How on earth though do you fill a casing with sand?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Yes, a rule of thumb is to make the casing pipe twice as large as the carrier pipe; however, most municipalities require a casing pipe diameter less than this rule of thumb. That "should" give you enough space if the carrier needs to be enlarged in the future. I am not familiar with sand being used to fill pipe (I work in the Southeast), only spacers are used.
 
To: 1503-44
Yes, the difficulties of working between with the railroad and DOT have been a big reason why we cannot just replace the one casing. Thanks for you advice.

To: LittleInch
The crossings are between 25-30 meter. It might not be possible to pull it but I thought I'd ask if anyone has done something like that before. As for the sand, once the carrier pipe is in place they blow sand to fill in the casing pipe.

To: AgMechEngr
Thank you for your advice. I've haven't heard someone using only casing spacers on the carrier pipe and was wondering if we needed new bores we could get by using a strong casing and using just spacers for the carrier pipe to possibly allow for upsizing in the future.

To: TerryScan
Spacers are used on the on the carrier pipe to make sure there is space around the carrier pipe then sand is blown in to fill the voids.

To: All

Thanks for your help!
 
Well try vacuuming as much sand out as you can then cut it and weld on an end plate and attach it to the back of a D9....

If you seal the pipe off and then flood the culvert might help as the line will float or get more buoyant.

If that doesn't work add another D9.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
I have worked in the southwest for 27 years and have always just used casing spacers in our bores. We usually upsize the casing so that if we have to enlarge a pipeline we can just remove the existing pipe and replace it with a larger one. This is for culinary water also. We have done bores under railroads, interstates, state highways and local roads. I can only recall reusing one or two casings, but don't know why it can't be done.
 
I suspect its usually just the bad economics. Provided that the existing casing is still intact, it could be resused, even for oil & gas service.

Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
 
You're not putting the water and sewer in the same pipe, I hope?

You'd probably want to run a camera through it to make sure it's sound, especially if it's a kind of pipe that might corrode or separate at the joints.

That might be why the RR wants the sand fill, so if the casing corrodes away, they won't have a soft spot under their track.

If you can get a vacuum excavator truck on site, it would probably clean your casing forthwith.

My glass has a v/c ratio of 0.5

Maybe the tyranny of Murphy is the penalty for hubris. -
 
Probably would get some settling if you removed the casing.
I don't think a DOT would allow removing the casing.

 
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