Diesel Fuel Black Steel Pipe 1

[MarieR]

I am working on a project with a 1" fuel oil supply and return line between a UST and a day tank under a generator. The pipe is specified to be schedule 40 black steel pipe, pickled. This is the same specification we have used for many years and have never had push back from the contractors. However, on this project, the contractor has asked us to waive the pickling requirement. I assume the pickling is to make sure the interior of the pipe is clean - the exterior will be coated with an epoxy paint that has its own surface prep requirements (part of the pipe is double contained underground and part is in a pipe chase across a driveway). I do not see that this is a standard fuel oil piping requirement. Is this an obsolete requirement passed down through the spec over many years? Can I delete "pickled" from this and future projects? Thanks!

 

[1503-44]

I'd just go with ASTM A106 Gr-B sch 40.
Frankly I've never pickled anything other than fish.

 

[TugboatEng]

In most cases pickling is unnecessary the supply fuel is filtered before entering the generator package.

If the generator is not shipped as a package and has lines connecting pumps and filters that are to be fabricated and installed by the user, in that case, pickling might be required. Also, if you have any piping between a section strainer and a lift pump, that piping would require some type of flushing but not pickling. There isn't a blanket yay or nay rule here.

 

[LittleInch]

"Black Steel Pipe" is so vague as to be meaningless but for a 1" diesel pipe is understandable.

Pickling is ok if you then use it fairly fast, but for this supply seems unnecessary.

Regardless you should have some sort of cleaning / flushing spec before use? A 1" foam bullet pushed by water or air would clean out most loose gunk or just blast clean oil free air through it for a while.

So not required IMHO.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[catserveng]

The cleaning and "pickling" process was common for many years in larger marine and power generation engines, probably had a lot to do with the fact most systems were field built and a final overall cleaning assured no debris would damage the fuel system.

I still see specs calling out piping cleaning and pickling for fuel and lube oil systems, many engine manufacturers are fairly vague on the subject, Wartsila and Mak both had very extensive procedures, I have attached a Caterpillar procedure that was our factory requirement when I did commissioning.

Before you decide to just ignore it, you may want to check with your customer or end user, I know Army Corp of Engineers and several other government agencies called out specific cleaning procedures for piping systems on engine installations.

Just to be clear, cleaning and pickling are two different processes, "cleaning" is done in multiple ways to remove dirt, grit, surface rust and other contaminants introduced during fabrication, storage, transport and field assembly. Pickling is a process to remove mill scale from the internal portions of the pipe generated during manufacture of the raw pipe material. Hopefully you will find the attached helpful.

Hope that helps, MikeL

 

[1503-44]

Since "black steel" pipe has no production, fabrication, or finishing specification, if you buy it, maybe you'd better pickle it. Give it 2 doses of Pfizer as well.