1. Home
  2. ⏣ General Metalworking
  3. Pass through pipe reducing bushing

Pass through pipe reducing bushing

I have a 3/4" pipe thread hole in an aluminum plate, and I need to be able to connect to both sides of it using pipe fittings, with the through bore size not so critical. I have been looking around the web trying to find out what to call a double sided reducing bushing, but so far no luck. Short of having one made, I'm wondering if anyone has had this problem before and what you did about it. FWIW, the fittings would hopefully be stainless, but there's no serious need for it other than everything else in the system is. Thanks!

Reply to
Carl M
Loading thread data ...

Search on 'bulkhead coupling'.

formatting link
formatting link
HTH- Carl (not the same Carl and not Karl)

Reply to
Carl Byrns

I've seen those, but not quite what I need. I have atmospheric pressure on one side of the plate, high vacuum on the other, and I need to pipe through a different pressure, so it has to fit the existing pipe thread (the plate is too big to take back to the machine shop, and I'd rather not drill it out for a baseplate NPT adapter, which might be too small) and let me connect pipe fittings on either side. Thanks for looking, though!

Reply to
Carl M

Now that's a possibility. If all else fails, I'll go that route. Good tip, thanks!

Reply to
Carl M

How about this: Use a nipple a few inches long, and run a pipe die up about half way. Run a pipe tap into the hole far enough so the nipple will thread in and come out the other side. Use plenty of sealant, since you may not have a good taper-to-taper fit.

Reply to
Leo Lichtman

I would take a 3/4 to 1/2 reducer, bore it out so a 1/2 nipple will pass thru, silverbraze or weld the nipple in place. That gives you 1/2 NPT male threads on both sides of the plate.

Reply to
Don Foreman

I use a half of a 1/4 pipe coupling, turned down to fit the bored out inner end of a 3/4 - 1/4 reducing bushing. Silver solder the two pieces together and you have your fitting. I made a couple of these to adapt propane tanks for my compressor. Gerry :-)} London, Canada

Reply to
Gerald Miller

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.