

Oil Pipeline Pigs - chatmasta
http://en.wikipedia.org/wiki/Pig_(pipeline)

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vool
Discovered this a few yeas ago when I wondered about the meaning of this sign
in Dublin ->
[https://www.flickr.com/photos/infomatique/10601153425/](https://www.flickr.com/photos/infomatique/10601153425/)

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K2h
Just remember to retract the probes delivering samples to external analyzers
-before- pigging the line, or you may do 10's of thousands of dollars in
damage.

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acomjean
I've seen these for water pipes who have minerals build up in them over years,
effectively reducing the pipes diameter.

