Need Help Identifying Thread Form

Here is the image:

Perhaps a variant of Stub Acme thread? Doesn't look quite right. What is it for?

It is off an attachment for an AWJ Drill Rod. I just found this out, and am going to contact the manufacturer right now.

Turns out this is oil field terminology. "WJ" is their name for the thread form, which is a tapered ACME thread. "A" refers to the size, with 1.75" OD being the smallest normally available drill rod.

Thanks for the help!

Stop by anytime.

As our British friends say, "The kettle's always on".

^{I can't remember any of them actually saying that, but you get the idea}

This thread is used because it is course _{(of course)} so it connects with few turns and it seals well.

If you've ever watched them pulling or installing drill stem, you've seen this thread.

Cheers.

I should have picked up better the comment in the OP "...drilling operation..."

I assumed (incorrectly) along the line of a drill press. I should have picked it up from the visible taper. It is, however, a form of the Stub Acme thread, so I was on the right track.

The AWJ thread is (it is said) impossible to cross-thread. This makes it a fast and reliable connection in a very fast-paced operation.

A lot of this kind of data can be found in Baker Oil Tools Techfacts which is available on the web. I believe this to be a cable tool joint (see page 12 of the Baker Tech Facts above)

Great link. Thanks!