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Best place to get an agitator???


LockHouse

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Hey have a 200 liter boiler that i would like to add agitation too. I would like to both speed up heat up time and avoid scorching issues...

The agitator would have to tri clamp onto a 3" ferrule and be around 16" from the top of the ferrule into the wort... I'd like to do this as cheap as possible and preferably an electric motor as apposed to an air powered. This is a commercial environment so i assume the motor would have to be explosion proof?

Any help or suggestions would be greatly appreciated....

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I think there's a lot of 'depends' in the answer.

If you're talking about a shaft/coupling/paddles combo, go to a local metal fab shop and sketch it out with them. Might need to consider torque issues too. dunno what you've got in mind for bracing/seal/etc, but if it's just a 3in TC fitting, clamped, etc., any robust motor would make short work of it. Gotta keep it sealed (assuming it's a still, not a mash tank) and keep it from spinning.

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Uh, depends what you are putting in the still. If it is water viscosity or close, a small air unit is cheapest. This is what I think the earlier posters were pointing you toward. Explosion proof electric much more expensive. If it is distilling an on grain mash or fruit mash with some viscosity, you will need a much bigger motor (and impeller). You can get air, but you will need a very big air compressor to drive it. And if you want one of these larger units, try Brawn in Holland MI. They will size/design what you need. But these bigger units can't sit on a 3" feedthrough without some additional support.

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Its only 50 gallons right? Thats like a turkey fryer size or slightly bigger, it shouldn't need to high torque for that even if polenta like.

Torque requirement is not proportional to volume. Way to think of it is you need a certain size impeller and torque do generate a lamellar flow for a given viscosity, not a given size vessel. You need something pretty hefty for a 50 gallon to do corn mash. I know, I have one. The small air-driven unit won't hack it. That's why we pump the mash for agitation instead.

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Pumping for agitation? That's a great idea, never thought of that. What brand/model pump do you use for that? I've got a 50 gallon boiler on order and want to do an on-grain corn mash but have no agitator in it. I could add input/output on opposite sides of the boiler so the pump output sets up a flow along the bottom of the boiler..

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Thanks bluestar, I read on a pump forum (guess there is a forum for everything) that a good rule of thumb is if you stick a pencil in a liquid and it falls over then a centrifugal pump can be used, if it remains standing then its too thick and a pd pump, screw, etc must be used.

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Bluestar, do you mind sharing what size pump you are using? I am curious what power rating the pump is, what size tubing you use and how many GPM you might be pumping. Thanks!

Not sure of the size, I got it for a steal used on e-bay, and it is a washdown. We don't have a drive for it, just run it directly off 3-phase 240v, its a Baldor motor. You can use a valve to throttle it down, if you need to. We use a 1-1/2" diameter hose, and we timed it at about 30 gal/min.

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  • 2 months later...

There are lots of options for pumps that operate below 212F. While a stainless centrifugal pump certainly fits the bill, they can be a pain to clean grain out of if you are fermenting on the grain. I've found that the ones we have (Thomas) to be sensitive to having too much particulate in the stream. A small March homebrewing pump can move some solids (ours actually moves glass shards pretty well) and is ok up to 212.

But if you're moving mash, the best cost-effective method is to use an impeller pump of some sort. I use a giant Jabsco with a VFD...we pump through 2" brewers hose, and this thing is plenty! If you're using a smaller still, I'd imagine there are some pretty good bilge pumps from Gould or Jabsco that would be great for mash agitation. If you spec an EPDM impeller, you'll be good to go to about 250 F.

I also use it to agitate my mash while heating it in the tun. Our steam jacket only covers about a third of the wall, so I pump the mash liquid in a loop to ensure even heating.

Given unlimited funds, I'd recommend a positive displacement screw or lobe pump. Or even a peristaltic with high temp hose...

Hmmm...I may have complicated the issue, here....

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EPDM will embrittle over time if run at 212F and above. Yes, it is chemically resistant at those temperatures. But it continues to vulcanize, and will eventually fail if not replaced as part of preventative maintenance. Even worse if exposed to high concentration of ethanol at those temperatures, but low concentration in mashes should not be a problem. But the rebuild kits are reasonably priced, as are the pumps.

We have found the SS centrifugal pump can be easily disassembled for rigorous cleaning, although we find running cleaning water (we let it do our CIP pumping for the still) through it cleans it up pretty well. We do grain-in mash for both corn and rye. It can be throttled back. But it can't self prime, a main advantage of the impeller. And it stalls on cavitation or emptying, for that reason.

I think what looks most interesting for us next is a large size diaphragm pump, albeit expensive. Self priming, variable speed, and if air driven, suitable for high proof alcohol.

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I hear you on the EPDM failure. But the impellers are pretty cheap and easy to replace...I usually hit them up once or twice a year as part of the maintenance schedule. Also, if you reverse your pump direction a lot, it will hasten impeller failure.

One of the issues I've had with the ss centrifugal pumps is that we use square tanks as fermenters. I get a big whirlpool over the exit port when I'm pumping at a reasonable speed, and if the centrifugal sucks air, I have to stop it and re-prime...

I do use centrifugal for CIP, though I don't want to use them for mash, cuz my cellar guys would slit my throat if any bits of grain appeared in their crystal clear Kolsch! I have to admit that when I'm transferring higher proofs I like to use a pressurized container and simply push with CO2,

I've used diaphragm pumps extensively on packaging lines, and although they are nice for some applications, I found that I was rebuilding them almost every other week. I found that was true in both low viscosity, low temperature pumping, and also pumping room temperature higher viscosity liquids...though they failed less at room temp.

We use a peristaltic pump for yeast, and as the pump tube is completely enclosed, I have envisioned using it as a high proof pump...it's got a great VFD, and though it isn't super high volume, it's adequate. I'll have to see how the pump hose holds up to higher ABV's. I have a chunk of it sitting in some heads/tails right now.

Didn't mean to hijack the thread! I might also point out that you can assemble a pretty good agitator out of parts found on Automation Direct for under a grand...minus the shaft and agitator blade. If you go McMaster Carr, it jumps to about $1500. If you maybe have a spare motor lying around with a standard NEMA 56 bolt pattern, a gearbox can be had for a few hundred dollars.

I came across an interesting idea on another forum today...guy was going to use a dairy homogenizer (which can often be had for relatively small money) running at low speed as an agitator. It looks like a clothes dryer drum in a horizontal jacketed stainless tank. The tank was equipped with high pressure CIP jets for cleaning, and was rated for 15 psi steam. His plan was to put a column on the dairy inlet flange, block the outlet flange, and load and unload the charge through the manway. I don't see why it wouldn't work.

My vote will be for the first guy with a bicycle powered agitator. :P

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Yes, but that's not really a big hurdle. A small Group D Div 2 motor is pretty affordable. Even Div 1 is fairly reasonable. I would recommend one that has an external fan if you plan to run it consistently, and remember that it will pick up extra heat through the shaft and connection to your pot.

Rated for alcohol vapor would be Class 1 Group D division 2 (not normally present, but may be accidentally). Division 1 would be explosive concentrations of alcohol vapor normally present.

Just reminder...it's important for your switch to also be rated. A good Class 1 switch is about $35.

However, I suggest the best prevention is to invest in good ventilation :-)

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  • 3 weeks later...

I'm interested in your definition of affordable explosion proof motors. Also, what sort of explosion proof switch is only $35? I just spent $160 just on a class 1 div 2 3/4" switch enclosure. Typically it seems like adding exp to a pump doubles the cost. That's why I'm going with air diaphragm for my spirits transfer pump. Haven't looked into agitators yet.

This thread didn't seem to answer the original question of best place to get an agitator, any other sources y'all recommend?

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  • 1 month later...

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