Fully Automated Brewing System Design

[praxis178]

Yea, will weld it myself, but I know I cant cut very well, and all three vessels have a conical bottom so I will have the stainless sheet cut for me. Thinking 2mm thickness? Would that be alright?

Been tooking on ebay for a tig welder. Whats a good price? will just be running it off a standard power outlet, I hope thats enough.



Thanks! some nice info there.

For a small 60%duty cycle ~200A inverter unit you're looking at 200-350 plus a helmet $50 to whatever you're willing to pay, (they're your eyes!). Then you have to rent a bottle of argon (BOC ~$20 for the gas plus $40ish/quarter rental for a small one). I have one i that class and it does a great job on SS upto 2.5mm above that it's a bit dodgy, but that may just be my welding unskills.

How big tanks were you planning on? 1.2 is used in most winery fermenters to 2000l, the smaller 300 to 1000l ones are usually .95mm from foggy memory.

 

[yardy]

Yea, will weld it myself

you purging ?

 

[Bandito]

Thanks Thomas, I didnt realise I needed argon. But I did know that sanitry welds required the inside to be purged with aron. So purging ay? Not sure. I know I should, will have to mull over how to seal the ends, and will probably need to slightly pressureise it to ensure oxygen doesnt get in. Of course, first I need to get some decent practise and learn how to weld!

So 2mm is probably heaps then, cool.

The issue comes where I think I will need to use a 6mm minimun thickness bottom flange to bolt to the butterflys. Do you think the kind of unit you mentioned Thomas would have problems welding 2mm to 6mm stainless?


I will heed the warning on the eyes, can you reccomend the best welding mask thats not one of those solar activated ones please?

I have had welders flash once, but it was not from welding. A few years ago I was experimenting with a solar concentrator to reflect the sun off 15 mirrors onto a single solar panel. I got a light activated welding mask from the green shed but it wouldnt activate in the sun! I had also got a pair of oxy goggles so I wore those. Towards the end of aligning the mirrors to reflect all of the suns light on a single solar panel it got bloody bright! I did also look directly at the sun through them for a few minutes - looked amazing!

But the next day I couldnt open my eyes and had to call in sick, then the next day I also called in sick, but could open them for long enough to call my opthalmoligist who told me to use cold eye drops and cold compresses to cool the eyes down. That worked a treat and was back at work on wednesday - albeit wearing sunglasses in front of the pc!

The solar concentrator worked and the solar panel put out 10 times the current that it normally does. It did crack from the heat though, and I ran away fearing the fumes from the solar panel. But I did learn not to take chances with my eyes. When I went to my opthalomoligist for a checkup he said I hadnt done any permanent damage to my retina - thank god! Was pretty stupid, I knew I needed arc class protection. And I knew that oxy (flame) protection wouldnt cut it.

I hope thats a half interesting story and show that I dont do anything by half measures.

Pics of the solar concentrator:

 

[praxis178]

Thanks Thomas, I didnt realise I needed argon. But I did know that sanitry welds required the inside to be purged with aron. So purging ay? Not sure. I know I should, will have to mull over how to seal the ends, and will probably need to slightly pressureise it to ensure oxygen doesnt get in. Of course, first I need to get some decent practise and learn how to weld!

Argon is way heavier than oxygen so all you have to do is stop it from falling out the lowest opening in what you're working on, cardboard and duct tape will work.

So 2mm is probably heaps then, cool.

Yep.

The issue comes where I think I will need to use a 6mm minimun thickness bottom flange to bolt to the butterflys. Do you think the kind of unit you mentioned Thomas would have problems welding 2mm to 6mm stainless?

Look at stick (electrode/rod welder) for that as I find I can get more heat deeper that way, it's a brute force thing.

I will heed the warning on the eyes, can you reccomend the best welding mask thats not one of those solar activated ones please?

Look for a min shade 14 old style mask, should be ~$20 at the big green box, you can get replacement lenses at any welding supply place. These will usually be of far higher quality than the originals (even if they say they meet the *minimum* standards).

I have had welders flash once, but it was not from welding. A few years ago I was experimenting with a solar concentrator to reflect the sun off 15 mirrors onto a single solar panel. I got a light activated welding mask from the green shed but it wouldnt activate in the sun! I had also got a pair of oxy goggles so I wore those. Towards the end of aligning the mirrors to reflect all of the suns light on a single solar panel it got bloody bright! I did also look directly at the sun through them for a few minutes - looked amazing!

But the next day I couldnt open my eyes and had to call in sick, then the next day I also called in sick, but could open them for long enough to call my opthalmoligist who told me to use cold eye drops and cold compresses to cool the eyes down. That worked a treat and was back at work on wednesday - albeit wearing sunglasses in front of the pc!

The solar concentrator worked and the solar panel put out 10 times the current that it normally does. It did crack from the heat though, and I ran away fearing the fumes from the solar panel. But I did learn not to take chances with my eyes. When I went to my opthalomoligist for a checkup he said I hadnt done any permanent damage to my retina - thank god! Was pretty stupid, I knew I needed arc class protection. And I knew that oxy (flame) protection wouldnt cut it.

I hope thats a half interesting story and show that I dont do anything by half measures.

Cool story!!!! And you're lucky you can still see, I've worked with high power optics 16" F3 mirrors so know the power of reflected light....

Pics of the solar concentrator:

Answers in italics above..... For what they're worth, I'm not a trained welder.....

 

[Bandito]

Thanks Thomas, thats a big help :beer: Much appreciated!

 

[Gout]

Bandito, it might be worth doing a short course in welding at your local tafe/trade school. I did one when i started to weld and it was a few nights over a few weeks, but you get lots of metal, gas etc to weld away. Esp with tig where you can contaminate the tip

I did the mig course as i was working on cars and it helped, however i would not call myself a welder. Better to screw up so scrap than a nice new stainless conical, welding is an art-form and i don't think you can learn it from books.

 

[Bandito]

Thanks, I'm not sure if there is a tafe here 13 feet left of the black stump - aka batemans bay, but will check it out. I plan to have the scrap sent to me too and practice on that. But I think it will take a massive amount of practice to get a nice weld going. But since I draft steel buildings for a living, I think I should learn to weld anyway. I reackon going out in the yard to weld on a day off would be good.

Can I weld normal mild steel with a tig welder? I have used a welder that had a welding stick in it - thats probably a tig right? It was easier than the mig I tried back in high school when I was 16yo! Couldnt get the feed/current right on that!

Yea, very newbi on the welding, but will hopefully learn some skills that will come in handy for all the intricate things that need doing - and there are several hundred of them in the current design! Hopefully doing it myself can reduce the costs, and if something doesnt work I can just redo it with no extra cost.

My new hard drive didnt arrive today, so I am going to use my normal software to model a mock up MLT / KETTLE to show what I intend on doing.

 

[Gout]

sounds like Arc welding you speak of....

Tig i feel is the hardest, i can not tig weld, arc i am rather good at and Mig i was getting very good at however i have not welded for some time so i would be crap. I find welding like spray painting, there is a fine line between a nice weld and going a tiny bit too far and blowing holes. Like a good cook without a recipe its all about feeling you just know when its right - this takes a lot of time and practise

I am sure tig can weld mild steel, if you get a tig they normally have a stick attachment also and these are much nicer to use than the old transformer arcs.

All that said, it sounds like you may want someone else to weld it for you. Apart from Al welding it sounds like SS food grade welding is the second hardest welding (pressure vessels would be worse ofcourse)

again i am not a welder but i shudder when i see how easy they make it look, their welds look like smooth fluid welds - mine.... bird shit

good luck either way, but i would try welding before you outlay the money.

Lots of welding shops let you try their welders "try before you buy" (thats what i found) Why dont you go and have a chat and try - it might help you decide

 

[Bandito]

Thanks, some nice info there - very realistic and doubt I will achieve much better. But I do want to try, and try I will.

And I hope that if I try and try and try again and again I might be able to achieve it - I refuse to accept that I cant do something - so I guess I need to call the matrix for a download.

 

[yardy]

a shade 14 lens will be too dark for TIG, or it is for me anyway.

i suggest you take the advice above and get some training or better still get a shop to weld it for you, some people take to TIG like a duck to water, others, not so much.. stainless can be a little unforgiving if you don't watch your heat, I'd hate to see you **** your vessels.



just my opinion though

 

[kirem]

for what it is worth I started a TAFE welding course at night. I have to do the basic course in cutting, oxyacetylene welding/brazing, ARC and MIG before I can go on to the next course which can be TIG welding. I was told learning to weld with oxyacetylene is very good training for TIG. My course is based on number of hours welding. I go for 4 hours once a week for 26 weeks.

I hacked around in the shed before the course. It is enormous learning value to have a teacher show you how to weld, then I put a few welds down and then he points out what I am doing wrong and I concentrate on those areas, more welds, more faults etc etc before long you can put a good weld down. then they ask you to weld at difficult angles, different thicknesses etc.

Unless you know what you are looking at a weld can look pretty good to the untrained eye and be full of faults and have no penetration.

I strongly suggest you get some training, perhaps if you have access to people that weld for a living, tell them what you want to do and ask them to teach you by looking at your welds and pointing out what is wrong with your welds and work on fixing those faults up, most of the time will be in practice.

If you can find a TAFE to help you learn, once you have their trust that you are not a dickhead, good bet they allow you to do you project using their equipment!

 

[praxis178]

a shade 14 lens will be too dark for TIG, or it is for me anyway.

i suggest you take the advice above and get some training or better still get a shop to weld it for you, some people take to TIG like a duck to water, others, not so much.. stainless can be a little unforgiving if you don't watch your heat, I'd hate to see you **** your vessels.



just my opinion though

Funny started with a shade 13 found it too bright, but I use an auto darkening mask, so set it to 15 and it's about right for me, it really is a personal thing, if you have great night vision go darker, if not you will have to go lighter, but probably no lighter than 13.... So yeah it is a subjective thing, and your workshop lighting also plays a big part, the darker the it is the more contrast you have, so you can go darker.

I found mig to be the hardest to learn (did the basic TAFE welding course) and tig to be rather like brazing which I had been doing for many years.....

If you haven't done any welding before, DO THE COURSE even if it means an hour or two in the car each week (I lived 60kms from the TAFE I went to).

 

[Bandito]

Heres a pic of the idea for the kettle and mlt - I think its way too strong. Just the straight part (not including the conical part) is 94L, but it is a bit fat so will make taller. Currently 27Kg using 2mm stainless, will probably go down to 1mm.
Also measured up the fridge. The volume of the straight part of the fermenter is coming in at 87L.

Still early days, but at least I have finally got something half decent in the model.

 

[praxis178]

Heres a pic of the idea for the kettle and mlt - I think its way too strong. Just the straight part (not including the conical part) is 94L, but it is a bit fat so will make taller. Currently 27Kg using 2mm stainless, will probably go down to 1mm.
Also measured up the fridge. The volume of the straight part of the fermenter is coming in at 87L.

Still early days, but at least I have finally got something half decent in the model.

The kettle looks a bit over engineered, but that's just a gut thing so don't mind me. :lol:

Go 1mm for the walls, 2mm for the cone section and ribs, and only have the ribs on the cone section and it will probably still be more than strong enough. Definitely a reason to invest in some FEA software if you can!

 

[Bandito]

Yea, thats a standard design for a 400 ton coal bin. With that design the whole thing should be strong enough with 0.05mm sheet! The thickness would be more determined by the weldability than the strength I think - but then there is cost too.

I do think the vertical stiffeners and horizontal ring stiffeners will reduce the stresses on the internal welds. So the joins between the straight and conical section will be reinforced by the 3mm continuous fillet weld allround on the horizontal ring stiffener. The lower vertical stiffeners are more to stiffen the bottom flange. And looking closer it seems it may need two stiffeners close to each bolt - which doubles the stiffeners. Looking at the attached pic, it seems there is a 3mm gap between the bottom flange and the butterfly bolt lugs - this gap might need to be filled with a high temp silicon compressible gasket. Just modeled the teflon seat which is in yellow.

The owner of my rental property came over today to re-attach the inside glass of the oven. And he used high temp red silicon from a caulking gun. That got me thinking about using that to seal between the stainless vessel and the teflon seat. I really dont think it will seal by itsself. I'm more inclined to get a silicon gasket atm, which should be standard.

Would love to get hold of a trial version of strand. Not sure if I will enlist the services of the strand engineers from my last job. Will probably just over engineer it so it lasts into my 90's.

Also atached is an overall view of the laundry so show what space I'm trying to fit it into. Havent placed anything apart from the kettle and fridge in months, so its mostly out of date.

3D MODEL ATTACHED ALSO: open widows explorer web browser, but doesnt work on all pc's.

View attachment jessica_brewery_4.zip

 

[Jono_w]

Hey mate,

Designs looking good.
I have concerns with all those fillet welds needed on the vertical and horizontal stiffeners the tank, these will be very difficult to weld without it warping the tank/cone significantly. Welding stainless sheet is a constant battle with warping. The cone has plenty of strength to hold a well made and welded flange without the stiffeners I think. Also, don't believe everything that fancy CAD software tells you, I have seen many situations of things totally over engineered to a point where they are not viable. I think a 3mm bottom flange with 1.6mm cone with no stiffeners would be more than adequate.

Cheers.

 

[Bandito]

Thanks Jonathon, I neglected to add the weld specification for the stiffeners. I agree that warping will be an issue. I was thinking of tack welding the vertical stiffeners on the straight section followed by a stitch weld - something along the lines of 50mm on, 150mm off, staggered on both sides, coming back and filling up the gaps - or mabee not coming back and filling up the gaps. Would that sound viable? Was intent on 3mm cfw allround on the lower vertical stiffeners though. There is a 3mm chamfer (cut) at all welded corners.

Unfortunately, this is just my main software I use at work, and it doesnt tell me anything - apart from clashes between steel and between steel and bolts - and the current setup does have a clash between the bolts and the first horizontal ring stiffener, so with the present setup will have to install the bolts from the bottom. It also looks like I need a manifold on the bottom of the butterfly to direct the grain and hops to a single false bottom then the drain.

It is hard to tell how strong something is. I keep thinking about my 35L SS pot, and it seems so strong, but when I look at this in the model without stiffeners it looks weak - I guess its my lack of experience on thin walled vessels.

A 3mm bottom flange with no stiffeners? you are probably right, especially if the torque on the bolts isnt that great, but I am planning on making them very tight - perhaps I should reconsider that.

Still quite early in the design, so everything can change. Thanks for the help!

 

[Bandito]

Having some slight space issues :huh: moving the fridge next to the door should free some up though, didnt think it would fit.

 

[bum]

Easy solution. What is more important? Beer or clean clothes?

Look at how much space you just freed up!

 

[Bandito]

No Bum, I will not be washing clothes by hand - that why automation was invented!

Theres now enough space for a nice fat 140L HLT. Was going to model the supports and bung with drain and heat shield for the plaster walls, but first I need to figure out how to support these butterflys.