Overflow filter bulkhead

[Easternlethal]

Hi all, I'm building a sump and relying on an overflow filter.

Unfortunately the shop I ordered the overflow from can't tell me the dimensions of the bulkhead. I know it is 40mm wide but don't know the thread dimensions.

I'd like to attach it to a pvc pipe which has a 32mm diameter using one of these.

Am I on the right track? If so, what specifications should I be looking for? My local hardware shop doesn't have anything which fits so I'm ordering online but I'm a bit overwhelmed by all the different measurements and fittings.

Thanks for your help!

 

[foxfish]

What do you mean by the bulkhead? The fitting that goes through the bottom?
If so, and it is 40mm then you need a 40 - 32 reducer, it looks like solvent weld PVC but it is impossible to really say from the picture.
You might have to wait until it arrives before you order any parts.
I buy all my fittings from a water irrigation store that is close to my home so it is easy to visit but not so easy to buy online.

 

[zozo]

Find out the manufacturer, could be USA a lot if not most sump related products are USA made, if so it probable has NPT thread. Than the standarized european britisch thread doesn't fit.. Is it Eurpean manufacturer? Can't realy find any info on Reeflive, only manufacturer using this term i can find is Aqua Medic which is German, also have overflow boxes. In this case the pipe thread will be british standard.

1" pipe male thread equals 33,7 mm (would be around 32 mm female)
1 1/4" pipe male thread equals 42,4 mm(would be around 40mm female)

 

[Easternlethal]

I bought this white thing which I think is a reducer and seems to fit the bill.

Only thing is the thread doesn't quite fit. From the markings it looks like a 'british thread' ?

 

[Chris Jackson]

If the thread is just a little off you can probably succeed by wrapping it with PTFE thread seal plumbing tape

 

[zozo]

If the male thread is NPT it has a slightly larger diameter than the BSPP, aproximately it's the same, but this little bit still prevents some combinations.

in the size you have the NPT has a TPI (thread per inch) 11.5 and BSP is 11 so this is fairly the same.. That's why BSP male fits in NPT female, tho it will be a bit lose because of the smaller diameter.. But beause of the larger male diameter NPT male doesn't fit in BSP female.. It might go in one or 2 threads and then it gets stuck. The TPI deviates more when diameters gets larger. Check your diameter and check the TPI in the aboves site diagram.

Things you can try to do is grind off the male thread diameter a bit with sandpaper till it fits. And use as Chris says a bit PTFE tape. Or dont grind it off and put on a PVC Union Coupling first put pressure PVC glew on it, because this one is more kit like and fills tiny gaps and screw it on as far as possible and reduce from there to 32mm pipe size.

That way you still have a rubber sealed coupling under the overflow box if needed.

Another thing which probably works is put the female coupling in boiling water, then it gets a bit soft, pliable and it expands, than screw it on thight with a rubber seal in it. Note once it is cooled and shrunk again, it might be pretty stuck and very hard to get off again without warming it again. so make sure it is water tight..