I have a piece of well drill rod that is 3 3/4” diameter steel and it is solid, not hollow. Any idea what kind of steel it is?

Is it a high enough carbon that it can be hardened? I have tentative plans to make it into an anvil.

I am no well driller. But my guess would be that something like that is already hardened.

quote:

Originally posted by jimmy123x:
I am no well driller. But my guess would be that something like that is already hardened.

Not necessarily. I’d venture that the bits may be hardened, but the rods would be too brittle.

I would think something like that, possibly a drill collar or something would be in an unhardened state to flex with the bore of the well.

Found a tip online recently.... If you have a TIG welder you can get a read on its carbon content by striking a quick arc on an edge, letting it cool and hit it with a file. If it skates over the metal, there is supposedly plenty of carbon content for hardening.

The theory, if I remember correctly is that the quick heating and quick cooling from the heat being sinked out by the mass of the part in question is similar to quenching the metal as they do in hardening processes.

It's not my end of the business. BBS is likely the most knowledgeable Sigforumite in this.

I do know enough to know that there are dozens of possibilities and some are very exotic alloys. Are there any markings on it?

Linky:

https://www.metalsupermarkets....-drill-rod-shafting/

I sold directional boring rigs which are a similar industry.

Typically drill rods are made 2 different ways. They are either forged and then the ends hardened or a hardened steel (like 4140) is inertia welded to the end of the tube. Either way, the end of the rod where the threads are is hardened. I guess I didn't know much about carbon content back then but I'd say the inertia welded rod end will certainly have a higher carbon content.

If in fact this is a well drilling rod and not a directional drilling rod, it's likely a forged piece.

Added information, should have included earlier - rod is SOLID, not a tube, near the ends are flats, making a square cross section for large wrenches to unscrew the sections from one another. I believe the threaded areas are tapered threads, but not certain.

While the steel may be of a higher carbon content, or an alloy (which is what I am trying to figure out), it is not currently hard. Pieces have been cut off with a metal cutting bandsaw.

A full length section is pretty close to 16’ long.

Might try the TIG idea, as that information would be more that I already have.

Have not yet checked the threaded section for hardness, will do that today. I would be inclined to think the rod is forged as well.

No markings whatsoever. 100% surface rust.

In this case it appears that two sections were screwed together on a job and they couldn’t get them unscrewed. They cut them apart with a torch, then scrapped them both. I bought the two 16’ pieces at the scrapyard.

Thanks for your thoughts guys -

Might be good material for a custom knife project!

I found the Video. The test I was referring to previously is at about the 1.30 min mark, but the whole vid is a worthwhile watxh for metal identification using abrasives.