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Looking for small tubing manifold

Looking for small tubing manifold

Looking for small tubing manifold

(OP)
Hello,

I'm working on a project where I need to connect 20-60 small diameter tubes (ID 1/16", OD 1/8") made of PTFE (or similar). I run compressed air through it at a pressure of 3-10 bar.

I'm trying to find a company that would sell or manufacture a manifold for my application (manifold with barbed hose, or something similar). I have currently have one for 20 tubes, made with barbed fittings on a threaded manifold (through mc master carr), but I'd like something more compact and if possible with more connections per manifold.

Any hint on companies I could contact / product similar to what I'm looking for?

Thanks,
Tom

RE: Looking for small tubing manifold

(OP)
The one I have looks exactly like the last one shown in your link Mike. I'm looking for one with more than 20 holes in it. But thanks, I'm going to call clippard, see if they can make custom manifolds.

RE: Looking for small tubing manifold

Most any machine shop can make barstock manifolds.
The only limit is how deep they care to drill the central lumen.

Last I heard, Clippard does do specials; at least some are subcontracted.

Their hex brass manifolds with 10-32 fittings can easily get to 20 ports.

The only problem I have with their 10-32 fittings is the default rubber gaskets, which harden and crack too soon. I don't use 'em at all; I use Loctite PST instead.

Push-to-connect fittings are a dream to assemble. They work best with nylon or polypropylene tubing. That's what I would suggest for your application, unless some unstated requirement dictates something else.

Barbs work best with polyurethane or heavily plasticized pvc. At your pressures I wouldn't use them.

PTFE doesn't work well with any connector The least awful connection for it is a heat-formed 90 degree flare used in chromatography. Expect a high scrap rate and low production rate if you go that way. Also a lot of burned fingers.



Mike Halloran
Pembroke Pines, FL, USA

RE: Looking for small tubing manifold

Agree with Mike on push-to-connect fitting (aka John Guest fittings, though I think the patent has lapsed and they are now available from many different mfgrs.) Rather than PTFE tubing, use PFA - has similar resistance as teflon, but is clear/translucent and flexes/works with JG fittings similar to PP and nylon.

RE: Looking for small tubing manifold

Hit the post button too soon again. If you peruse the John Guest catalog, you can find the parts to build push-to-connect fittings directly into the manifold you have manufactured. Reduces the space required by a fair bit, and easier assembly (the pieces for the ptc fittings snap-fit into the manifold housing).

RE: Looking for small tubing manifold

(OP)
Barbed fittings are more suitable for me because they take less space and are cheaper to implement. Also once the tube and the fitting is attached, I won't need to actually remove them, so I'm fine with the barbed fittings. The PTFE I have at the moment is clear and the properties are fine for what I'm doing. The most important thing is the max temperature. Do you see any other reasons for me to swap to PFA?

About the Manifold, I found a company called Memco that does specialized manifold, especially one catched my eyes: https://docs.google.com/file/d/0B-8jLWfdkWpIZjQ3an...
That's exactly the kind I'm looking for: very compact manifold

If you know other designs close to that one, feel free to share.

Thanks,
Tom

RE: Looking for small tubing manifold

I have never seen PTFE that was truly clear, so I'm not sure what you have.
Burn some to check.

If you're planning to push anything as slippery and as stiff as PTFE on tightly clustered barbs, expect a lot of hand injuries. ... and a lot of small leaks where it loosens, and a lot of bigger leaks where it splits.

Mike Halloran
Pembroke Pines, FL, USA

RE: Looking for small tubing manifold

(OP)
The PTFE I have is the "high temperature" one from Mc Master. It's not fully clear, but to be honest that's not a big deal (not really important for me). I have been using barbed fitting with the PTFE tube, both with and without tube clamps, and it worked without problem for pressures up to 10 bar. I've worked out a way to put the tubes without injuring my hands so that's good :)

So I'm continuing in this direction right now, until I have other issues. I tried some PFA tubes too which worked well. But I have to do further pressure/temperature cycling to see which one works the best for me.

Thanks for your remarks Mike

RE: Looking for small tubing manifold

(OP)
cant find a way to edit:
*thanks Mike AND btrueblood

RE: Looking for small tubing manifold

PTFE is not clear, it is opaque white. What you likely have is FEP. There are three different types of Teflon; PTFE, PFA, and FEP. FEP is translucent and make nice tubing. If your process needs to be reliable I would not consider using barbed fittings and plastic tubing on air at 10 bar. Plastics creep and the tubes will slowly expand and eventually pop-off. Push-in fittings don't really take much more space and are easier to use. The tubes can actually be removed without damage.

RE: Looking for small tubing manifold

(OP)
This is what I have: http://www.mcmaster.com/#catalog/119/144/=lvlofw , as I said it's not clear (I used the term "not fully clear" instead of "semi clear"). As mentioned I'm using tube clamps to avoid an accidental pop-off. I might give a shot to PFA tubes with push to connect fittings. Problem is the ones I usually find are in plastic and brass, my current manifold is in Aluminum and I'd like to not mix metals. Also with push fittings I wont be able to do very small manifold like showed in previous post.

I know plastic is not the best for the job, but it's a temporary solution. I need to find replacement for the long run, but that's not my priority right now, I need to find an expert in tubing and connection :)

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