Piggability Criteria

[DudePipeliner]

I asked a question about pipeline pigging which it seems misunderstood!

I know that the ID is finally important matter for pigging, but I don't know which items shall be accounted for?
lets say that the pipeline has two sections with 14.3mm and 15.9mm wall thickness.
so is the ID difference along pipeline is 15.9-14.3?
or should I consider some 10% wall thickness tolerance:
(15.9*1.1-14.3*0.9)
or should I consider OD tolerance either?


Pipeliner Dude
Offshore Pipeline Engineer

 

[MReddy]

Hi Pipeline Dude,
Piggability criteria starts with ID of the pipe.
Typically if it's mechanical pig (caliper pig), the disc size/OD is 95% of pipe ID. Therefore, use the smaller ID with 95% of pipe ID for disc OD.
If you are thinking of foam pigs, typically foam pig is OK for any two API pipe sizes. Say if you select foam pig for 16" line, it works for 12" line as well. We need to pay attention to density of foam to make sure it works.
Hope this clarifies.

Regards,
MReddy

 

[WilliamPMG]

Dudepipeliner

My background is in freeswimming heavyweight MFL tool design.

From my standpoint I would be concerned with just the IDs of the pipe. In particular, I am generally concerned with the minimum ID in the line and not so much with the variations of the pipewall.

Data analists will use actual wall thickness of the pipe when sizing defects.

If you just specify the OD and the wall thickness then anyone who is interested can work out the information they require on their own.

Hope this helps

William

 

[BigInch]

Also keep an eye on bend radius and valves that are not full port opening.

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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

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