Help me identify this fitting thread

[Stigma]

My measurements (these are not perfect, just as good as I could get them with my availiable tools):

Diameter (outside of threads): ca 17mm
Distance between threads: ca 1.4mm
Not cone shaped as far as I can detect.

From my own research (I'm not good with piping) I suspect it might be a 3/8BSP or socalled British Standard.
Source: http://en.wikipedia.org/wiki/British...rd_pipe_thread

Is this the same as a G3/8?
In other words, can I use this for example in the same thread?:
http://www.frozencpu.com/products/71...01&id=C5xqMKZJ

-Stigma

[coolmiester]

The barb you have pictured looks like a 3/8" BSPT thread (the T standing for tapered)

The barb you linked to is a G3/8 which is a parallel thread.

I guess the bottom line is what the barb is for.

[Stigma]

If by "tapered" you mean it is slightly smaller at the end than at the base, then I am uncertain.

I cna measure a difference, but it is very small. Only ca 16,6mm at the thinnest and ca 17,2'ish at the thickest. I am unable to distinguish if this is by design (if this is how a tapered thread looks like), or if its just a result of some corrosion over time or something. Perhaps you can tell me if this one I allready have is indeed a tapered thread?

The only thing I know for sure is that the fitting in the image I provided fits into my HXs threads. Thats why I thought it would be as easy as identifying what threads those were and just buy new fitting with the same threads.

Now that you have explained to me that there is a difference between paralell and tapered threads however, I suspect that tapered threads would fit into paralell threads, but not the other way, am I correct?

Therefore, if you concolude that the one in the image is tapered, then I can still not say for sure whether or not my HX's thread is paralell or tapered. Is my logic correct in regards to this?

If thats the case I suppose I can only resort to contacting the supplier and see if they can tell me what kinds of threads they send me on my unit...

-Stigma

[Dualist]

A male taper thread will fit either a female taper or parallel thread providing you have some PTFE tape on the male part.

[Stigma]

A male taper thread will fit either a female taper or parallel thread providing you have some PTFE tape on the male part.

Thanks! thats what I thought.

I searched around and was lucky enough to find that I actually had one plastic fitting that was pretty much identical to the one in the picture, except that it was definately NOT tapered, but equally thick all the way.

I tried that in my HX, and it fit like a charm!
While tapered threads git in paralells, logic dictates that a paralell male connection can't fit into a tapered female connection (atleast not very deep).
That means that the threads in the HX must be 3/8BSP right?
It also means G3/8 like this will fit, correct?:
http://www.frozencpu.com/products/71...tml?tl=g30c101

Thanks in advance
-Stigma