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what is pigging 2

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Pigging is passing a solid plug through a pipeline. The plug is small enough to pass through the pipeline but large enough to touch the inside wall. They have many uses - separating product, cleaning the pipeline, measuring the pipeline's wall thickness, etc.
 
In the James Bond movie "The Living Daylight", James Bond helped a general to escape from the Sovjet Union through a gas pipeline, by launching him from a pig launcher. You could say the general was the pig in this case.

Sorry, just had to post this.[bigglasses]

regards
Mogens
 
As IFRs said, a pig is a solid plug to be run through a pipeline.
Some of them are the so called pipe inspection pigs.
Its function is to assess the pipe for obstructions, corrosion (i.e. wall thikness), coating quality, etc.
Modern sofisticated pigs have scratchers and sensors (typically resistivity sensors in pads), and electronic means for storing and transmitting the data.
A pig louncher is usually a dead end segment of the same pipe conected to an elbow close to one end of the pipe.
The pig is lounched and pushed by pumping fluid (which could be specific for the operation or njust the regular fluid transported in the pipe).

check this site for different kind of pigs

I hope this helps

Fernando
 
Just don't forget that in Saudi they're called "Scrapers" ("pigs" is just TOO rude), so you get intelligent scrapers, gauge scrapers, scraper scrapers....
 
I was at one pigging station in Saudi and the words "Pig Launcher" stenciled on the side of the launcher had been changed to "Big Launcher". I was scratching my head initially trying to figure out if this was the "Big" launcher, where was the "Little" launcher?
 
Also see for in-line blending and automated pigging. Great techolongy for those dealing with gasoline and lube blending.

We load multiple products into railcars over a 1000' distance using automated pigging that pigs the line to the car and then back to the blender between loads to prevent contamination. Load a recipe, click a button, and the system takes care of the rest.
 
Totally agree with mgp for the “pig” definition!!! And as much stars he got the much he cleans.

Good sense of humour

Regards

Luis
 
There is a special form of "pig" used in meter provers. In this case the pig is usually a sphere which provides an intereference fit in the pipeline (it sort of pressurised ballon).

The prover is a section of pipe with a "sphere" launcher and catcher at each end. The sphere is a special form of pig. It forms a positive seal between incoming and outgoing fluid.

With flow from the flowmeters diverted through the prover, a sphere is launched into the flow at the start of the prover and caught at the other end. As it passess through the prover it passes a number of sensors which precisely locate its position and time at that position. Thus the volume of fluid displaced through the prover and rate can be very precisely determined. This data is then correlated with the flow meter data to calibration check/correct the flowmeters.



JMW
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You have to be careful though, launching sphere pigs down a line with barred tees designed for conventional pigs can lead to tears.....if you think you may use sphere pigs, put sphere tees in your line!
 
TD2K
In Arabic I don't believe there is a "P" sound, though there is in Farsi. Hence the "Primus" lanterns blowtorches etc were re-named "Brimus" for the Arab speaking world. This change is then reflected in the Romanised name. So this might be the reason behind the changed label.

JMW
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Why Pig?
This quote from an article on meter proving (answers the question:
One early positive displacement method utilized in the pipeline industry to prove meters inline on the flowing product was to install an inflated or liquid-filled elastomer sphere or “pig” in the pipeline with launching and receiving stations. The term pig came from the squealing sound the sphere made at low velocities, or with nonlubricating fluids.

JMW
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The first use of pigs were in the late 1800S this is where they most likely got thier name. They used barbed wire and straw in a ball shape, the noise they made going down the pipeline sounded like the squeel of a pig, Hence the name.
Since then Technology has come a long way, The pigs have evolved and got smarter they now carry computers on board, so you see now we have dumb pigs and smart pigs!And dont forget the magic pigs, they actually dissappear!
 
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