How about extreme cold?
So in the case of extreme cold…your joint is sealed by displacing material by forcing it outwards into the tube sheet. The shrinking of the metal joint, in extreme cold, could be a problem, as you would lose some of the force in the joint. We dont apply any sort of refrigeration…we use seawater.
The engineers I just spoke with said I could “do the math” to figure out if the joint would hold given the shrinkage rate of material per degree etc…I assured him I’d get right on it lol
He said they regularly see a few hundred psi max.
I should see if these tools fit in my back pack for a field trip.
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i haven’t broken any of our welded falling films at -70 with ~50psi. i trust that more than friction fit.
this is our ONLY failed falling film unit. look at that glow.
Is that your steam generator, or preheater? Ballzy running with that open flame!
I really like the idea of a swaged connection, but my monkey brain dosent seem to trust it yet. I got to get on the phone with this company, perhaps they can put the last nail in this coffin…I mean this tool is used in everyday industry. Can’t be any worse of an idea than a roll tap!
I think it’s certainly worth investigating. Not having a welded joint would cause some concern.
The joint has nothing to do with friction though. Metal is rolled, and displaced.
I wish I was closer…I could visit with some tooling for some joint testing.
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Ohhh joint testing, do we smoke them lol?
Just kidding Ya! What parts of the country are you in again?
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I’m in Wa. Puget sound area.
Lol I just woke up…didnt even catch my own pun lol
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damn, oppisite sides of north america!
Looks like it’s set up like a “spray-vap” are you using tube in shell or just jacketed spools?
Y’all could meet in Eugene 
not quite 1/2 way between, but makes it a single day drive for both of you!
…@photon_noir and I are looking to get into FFE manufacturing too.
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On Monday I’ll go lay eyes on the tooling to see how feasible this truely is on my end…
Let me do some research in design/tolerances of the tube sheet…pick an engineers brain…I’ve made a few big tube sheets a few years back and recall I wasn’t happy with the hole tolerances…but that could have been because there were 400+ holes on each part. For a proper test, I’d have to draw up a tube sheet with holes sized appropriately for the swaging, and make two. Totally within the realm of possibility…but I’ve got some foot work on my end.
Is there a Tig welder in eugene? I’ve got a machine here.
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what kind of machine, do you have other stuff like rotators or purge plates? I could make the tube sheets, got a laser.
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Lots of great TIG welders in Eugene. I’m not one of them, but do have a scratch start in my kit, and plans to get better at it.
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For tig…I’m a redneck in his garage with a syncrowave 250 from the 1990s…with glass tape to cap for a back purge. Your far better off than I Soxhlet.
The tolerances on the holes might be a bit tight for a laser unfortunately. If I remember I had to hold a .002 diameter tolerance on the holes, but my memory isnt the best. And the heat effected zone of a thermal cut may not lend itself to being rolled. When I make test coupons for destructive testing they dont let me cut them on the wire EDM. There is a minor heat effected zone, like .0001" that the engineers say will effect their test. I’d like to call bs on that…but with a laser the heat effected zone is greater and could be of concern. Roundness may also come into play with a laser or water jet.
I’ll do some digging tomorrow…
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I started on an open flame/can of sterno with no actual temp monitoring when I started with alcohol distillation a few yesrs back:sweat_smile:
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Sorry for the delay. Having some significant issues at work.
So having a few thousands slip fit for the tube to tube sheet joint is fine, I was under the impression the required tolerance was tighter. The tube sheet thickness is usually about 3/4 to 1" in thickness, but our coolers are usually pretty large, but still utilize a tube that’s about 3/4" in diameter.
When I was talking to the heat exchanger master, he was saying that new manufacture is a breeze. We mainly repair heat exchangers…retubing them etc, and my only experience is on repairing. I was led to believe anyone could roll these tubes into a new tube sheet with an electric hand drill. They use pneumatic tools…but that’s because they have fancy shit. He said I could use a damn dewalt drill. So the initial investment in in the rolling tool…nothing more.
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If you wanna ship prototypes to be welded I’m in the machine shop of the nation and up to my ears in skilled welders- local shipyard builds high tech prototypes for the US Navy and brings in extremely talented folks. I’ll be posting pics of the work that’s coming back on my wiped film build soon just got all the parts cut
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I do the work you speak of. None of my work is cannabis related. I’m here for hobby BHO and SPD stuff. I was just trying to relay info, and or technical knowledge of the process, and be supportive of those who have lifted up my hobby game.
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