Disconnects and Blichmann 3 piece ball valve

[neal.p]

Hi,
Is someone familiar with the compatibility of these two parts?

I've just tried to connect a 1/2 NPT male to 1/2 female quick disconnect with the 1/2 Blichmann 3 piece ball valve and quickly found that the disconnect has a tapered thread. I guess the disconnect is BSPT and I need BSPP? Or can I just make do? :unsure: I bought them in November and found out while trying to rebuild the system. The shop didn't describe them as tapered or otherwise.

Bah, I was hoping to do a leak test today.



Cheers,
Neal

 

[Lionman]

I suggest you speak with your retailer as we don't really know exactly what you bought, or if the retailer has sent the right parts to you or not.

Were both listed as being NPT?

 

[Mr B]

I dont really get the question. Exactly what are you trying to connect?

Nipple > Ball valve > Female disconnect?

Does the nippele go on (should be tapered?)?

Is the ball valve and/or disconnect tapered (should be able to tell by sight or measure)?

Whats happening? Do they screw in partially?

So mate, bit more info and should be able to help.

 

[Lyrebird_Cycles]

BSPT and NPT are both tapered but they are mostly incompatible. Likewise BSPP and NPS which are both parallel (straight thread) but also mostly incompatible.

One is Pommy, the other is Septic, in most sizes the thread pitch is close enough to look as if it will work but won't actually do the job. That being said IIRC 1/2" is one of the few sizes with the same thread pitch (0.0714" or 14 TPI) so maybe there's another problem here.

The adapter in the pic looks like 1/2" x 3/8"; 3/8 has two different thread standards: BSP is 19 TPI and NPT is 18 TPI. You'll get a few threads in and then it will bind.

 

[TehCrucible]

Keg King made a talking about this a few years ago. Might be of interest.

 

[neal.p]

Thanks guys.

Interesting video from Keg King mate.

The smaller threaded male end of the adapter is tapered. While the female thread on the Blichmann is parallel. The tapered end would only go in one and a bit turns before I could feel binding...which was worrying.

I read a bit about it on another other forum, and the consensus was wrap with 5-7 turns of tape and then keep tightening beyond the initial resistance. You can see in the picture that it's probably tightened 3-4 threads. I still to leak test. In any case the shop sent a different part to what I ordered.

 

[Camo6]

Looking at the pics I'd say you're using a 3/4" to 1/2" adaptor to join the tap to the outlet. While the above advice is spot on, if you're only using the outlet to drain wort, a few layers of pink thread tape and a leftward poking tongue will make it serviceable. If your apparatus is intended to create metallic hydrogen you might want to try a different approach.