[Open Source Design Project] - Falling Film Evaporator


Could this cap help with bho?



I wonder if they make an all stainless food grade . that’s explosion proof, sparkless and is rated for -80 liquids one.



When we manufacture large coolers/heat exchangers, we typically use a copper nickel alloy, but the tubes aren’t welded into the tube sheet(the plate with holes), they are swedged. This process is used by a massive company that has thousands of heat exchangers around the world. The process may be applicable if using like a 1/4 hard 304. This process may also allow you to easily manufacture your column with the tubes extending a small amount.

I can ask the heat exchanger big shot at work what he thinks…he’s only been doing this for 30 years.

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that is one method of distribution. the volume required to sit in the tray may not go well with your project scale.



I’m entirely new to ffe so I would like to know how are they heated/cooled. If a heating/cooling exchanger is a good idea or needed how would I go about building one? I’m looking to do 5-10 gallons an hour . are these closed loop? Would I need a fume hood at all?



Not that it’s the current topic, but I asked some questions today at work…one section builds and repairs heat exchangers. This info could prove to be valuable to someone along the way.

They swedge their tubes into the cooler, between tube sheets, with no welding. They typically reach up to 3 inches into the tube, and swedge the tube into the tube sheet, creating the seal. This process should work on stainless. It takes them 30 seconds at each end of the tube with a pneumatic swedging tool. The tube can project above the tube sheet as was desired in an above post. This is the way we build heat exchangers…and have done it this way for a very long time.

The upside is a very quick and easy process for creating the joint between the tube and tube sheet. The downside is in turn you’ll have tighter hole tolerances on the tube sheet holes, and will probably need thicker plate for the swedging, increasing the cost of that single component of the heat exchanger.

The guys at work literally tried to give me the swedging tools to do it lol. I can provide links to the off the shelf tooling to do it if I get off my ass and look.



You got my interest, lets see them tools!



Fuck me…I’ve been spelling it wrong. Its swaging.

Anyway…the guy primarily uses this brand.

I imagine this is the ticket for this application

There are options for hand held drivers. At work they use a big heavy fucker…but ther do 1000s of tubes…

There was another brand but I’ve slept since he told me…I’ll get it again.

If someone is actually interested in this process, there are brains I can pick from engineers to the tradesman. I’d say my passion for cannabis is only rivalled by my passion for manufacturing…so I get off on this shit.

And I’d love to get actual pictures of this…to actually show the finished joint and process, but I work in a secured area with no camera phones allowed…



Does their webpage have any photos of the process? This looks similar to the tools they use to make boilers.
Edit: the tool vendor has a nice vid of the process.
So these don’t need to be welded after the fact?



No welding required. They pressure test and call it good. And I dont think they have issues with that joints reliability. The tube walls fail first usually…at least on the big condensers I’ve stood inside and worked on.



thats slick



It really is superior in efficiency if you’ve got a few of these to make…



What pressures/temps are these joints good to? Ever have an issue wih cold and heat changing tolerances, and causing failures? I imagine If you could swage the tube into the plate, then use a copper electrode on a resistance welder to get in there and acheive true fusion?

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So our application is steam usually, or cooling a hydraulic fluid etc, I’m not sure on the exact temps these joints see, but its warmer than you’d ever want cannabinoids. The steam is under pressure…so it’s hot hot.

I’m off work today, but will be in tomorrow and can inquire about operating temps with the tradesman and the engineers.



We also use these two companies for various tooling as well. I forgot the names previously when I posted before…had to text the heat exchange master on my day off lol





I love the scrubby! :heart_eyes:



You probably wouldn’t achieve true fusion, because the current from a resistance welder is still going to take the path of least resistance, you can’t ensure that the entire circumference of your swaged tube end is going to have the same amount of resistance.

There’s also some question of how you’re going to keep the hot metal from oxidizing, without a very good argon shield you will get some nastiness and that will create a point that either attracts corrosion or possibly even a stress riser that could be a point for a failure to originate.

The way swaging works is similar to how rivets work, and keep in mind that 200 years ago hand forged rivets held together boilers on steam engines, with pressure differentials higher than what most of us are doing or trying to do with our FFE’s

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Im exited about this tool, I showed @Indofab who is a tool fetishist. He immidetaly wanted one.



I wanna try using a wiper assembly running fast to distribute the liquid more evenly



These things see 475 degrees in our application. I’ll inquire about pressure. But this is how boilers are made…so I’m guessing these joints can take significant pressure.

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