What's the lite coating on black iron pipe?

[stuckmotor]

When welding, I don't like the smell of burning paint on black iron pipe or care to breathe it. I tried soaking some in white vinegar. After a couple of days the paint came off easily. Recently I picked up a 12' stick at Lowes and the coating is much thinner and stains my hands like the grease on new steel from the steel supplier. It seems to be part paint and part grease. Anyone know what's in it?

 

[5030]

Schmeg....

 

[Redlands Okie]

From my limited knowledge......Depending on the pipe it’s probably a varnish like product. It also could be a tar like coating. Depending on the planed purpose of the pipe.

Brake cleaner or carburetor cleaner or lacquer thinner will probably work fine on the varnish or oil coatings. Watch your eyes (safety glasses a good idea) with these products and best wear protective gloves.

The tar like product I do not have a lot of experience with. Would try the same products or sanding it.

 

[tomplum]

You want to forgo the brake cleaner for welding. Toxic gas can be created. I would use a wire wheel to start with.

 

[Tractor Seabee]

Yes it is usually a varnish for short term rust prevention. We just burned it off a few inches back from the joint using our cutting torch at high O2 in the flame. When time is important you do what is the quickest. Working with pickled and oiled pipe is the worst. That was used a lot for lube and diesel oil and gasoline. Hydraulic also.

Ron

 

[WranglerX]

You want to forgo the brake cleaner for welding. Toxic gas can be created. I would use a wire wheel to start with.

Brake cleaner is fine as long as it does not contain tricloralfourethene(sp?) It's the "tri-clor" that converts to PHOSGENE (nerve gas) when introduced to flame/arc ...

Dale

 

[Redlands Okie]

Good information to have

 

[Raspy]

Some black pipe does seem to have a varnish coating, but the stuff from Lowes is more like a black grease. Some kind of oil based preservative that stains whatever it touches.

I'd definitely remove it before welding over it, and a simple oil based solvent should be fine for that. Paint thinner, for instance.

 

[polkwrangler]

Chinese pipe keeps from rusting during shipment

 

[tjkubota93]

Chinese pipe keeps from rusting during shipment

Cosmoline?