Valve & Pipe Flow Stoppage Problem 1

[AmyDesrochiers]

We suspect a line is not capable of flowing its full capacity due to the above ground piping, we have a few pictures but can't share here.

Line is an 8" line and open N/Gas flow through the 4" but we do not know how the 4" above ground piping is tied in. We do not understand why when the valve on the 4" is closed, the flow stops.

Someone has similar experience, please help with this critical operation issue. Thank you.

 

[BigInch]

You must find out how the 4" ties in to the 8". That's the only way you'll ever understand how your system works. If its a gas company line, give them a call. If its your's, go looking for old drawings. If you don't find them, get out your metal detector and hand shovel.

Going the Big Inch!

http://virtualpipeline.spaces.msn.com

 

[STYMIEDPIPER]

Is this a repeat question??
This same question was discussed within past month.
My guess is that a new 4 in line was installed above ground at some later date than the buried 8 in line. For reasons unknown at this time a decision was made to dead end the existing 8 in and tie into it. Thus, the 8 in is acting as your transport line. The 4 in above ground is your primary supply. The 8 in is no longer supplied from source even though drawings may depict otherwise. Drawings are not always updated to reflect various changes.

 

[AmyDesrochiers]

Thank you very much for your analysis. I agree with you about the tie-ins of the 4" line.

 

[AmyDesrochiers]

Big Inch:

I read your website, it's so interesting. You are very dedicated to explain about pigging operations. I tried to look at the map, map doesn't exist anymore. That is too bad for folks wanted to learn. Do you have another link where I can look at the Pipeline Network in U.S.A. and World.

 

[BigInch]

Amy thanks for the site complement and letting me know about the map access problem. I've been having some trouble accessing that site lately too. The maps are there, but are taking forever to load. I'll see what I can do. Maybe divide them up into continents or something. Drop me an e-mail (find it on my profile page) and I'll send the US pipeline map to you, or tell me which ones interest you. In the meantime, you can look at these,

Spain Oil Pipelines,

http://www.clh.es/CLH/Plantillas/conImagen/mapa.htm

Germany

http://www.eon-ruhrgas-transport.com/deutsch/default.asp?content=/deutsch/datenschutz.htm

You can download an Arcinfo file of the US GOM pipelines here,

http://www.gomr.mms.gov/homepg/pubinfo/repcat/arcinfo/index.html

New gas pipeline projects to Europe,

http://ec.europa.eu/ten/energy/documentation/doc/2004_brochure/natural_gas_network_prior_en.jpg

Mexico,

http://www.gas.pemex.com/PEMEX_Gas/...aestructura/Ductos/Transporte+de+Gas+Natural/

I must get a real website....

Going the Big Inch!

http://virtualpipeline.spaces.msn.com

 

[lookintomyeyes]

BigInch I'm pretty sure you're at least half-joking by saying "get out your metal detector and hand shovel", but...

...please use proper equipment when looking for natural gas lines. My employer has a fairly large natural gas pipeline system, and standard practice is to use a special line locating device (which will either detect a tracer wire or the actual pipe, depending on whether the pipe is plastic or actual metal.), then excavate a maximum distance above the pipe. The remaining soil must be uncovered using handdigging methods (not with sharp objects!), or by using a water-vaccuum truck, to clear around the pipe.
If the pipe is significantly deep, and there is the chance of a worker entering the created pit, shoring may be required to ensure the surrounding soil does not cave in.

If it's possible the pipe is old and leaking, wearing flameproof clothing may be a good idea - I've seen video footage of workers caught in a pit when a small spark lit set the natural gas on fire - not pretty.

 

[BigInch]

Consider it a tongue-in-cheek remark, if you have the locating equipment available, but by shovel, I did mean a hand shovel. On the current biggest pipeline project in the world 1700 miles of 42", the central spread contractor showed up without anything to use to locate existing pipelines in the right-of-way. Fortunately, Turkey does not have a lot of petroleum pipelines and the ones they do have are well marked. They did manage to break pleanty of water lines though.

One other note. If its not your pipeline, call the gas company [COLOR=white red] BEFORE[/color] you dig.

Going the Big Inch!

http://virtualpipeline.spaces.msn.com

 

[stanier]

Pipelines of Australia.

http://www.pipeliner.com.au/map/map.html

Geoffrey D Stone FIMechE C.Eng;FIEAust CP Eng

http://www.waterhammer.bigblog.com.au

 

[BigInch]

Excellent!

Didn't have that one in my collection.

Thanks

Going the Big Inch!

http://virtualpipeline.spaces.msn.com