Template for perf plates

[CH3CH2OH]

If some experts could provide some input I'd appreciate it!!!

Here is my proposed template for my plates that will be going to the waterjet guy for cutting.

Plates are 1/8 " plate with 3/4" downcomers into a 1 1/8" cup soldered onto the downcomer suspended 1/4" above the plate

3.90" diameter plate = 11.94 sq in (template is 3.92 but plate will be sanded to fit inside a 3.90 ID column)

224 holes at .0785" diameter = 1.08 sq in

this makes the holes 9% of the plate

everything look good before I send these off??

[bt1]

Howdy,

can't help here..

If some experts could provide some input I'd appreciate it!!!

but a few questions...

Top plate clearly a different template cos no cup area.
If the downcomers are suspended above the plates why do you need the cup blank per plate?
If they are suspended why not make them shorter so you have a more random spill back?
If the plate is being sanded or lathed back you'll need a small band of exclusion around the edge

hole size is std at 2mm but what hole centre spacing are you going to use .197"=5mm
I've used 1" caps on 3/4" downcomers as it was a std size= cheaper and they work well....might be a cost advantage to be had here

cheers
bt1

[bt1]

Oops almost forgot...

Also consider a small band of hole exclusion around downcomer for soldering in.

bt1

[Brendan]

:text-imwithstupid: :text-+1:

[Bushy]

Why solder the cups?
Mine are just a piece of 1" tube with a flared end that just sits on the plate. They work just as well as a soldered item

2013-03-17_07-03-29_20.jpg

You can't really see it here, but those cups can slide up and down the downcomers.

Bushy

[CH3CH2OH]

but a few questions...

Top plate clearly a different template cos no cup area.
If the downcomers are suspended above the plates why do you need the cup blank per plate?
If they are suspended why not make them shorter so you have a more random spill back?
If the plate is being sanded or lathed back you'll need a small band of exclusion around the edge

hole size is std at 2mm but what hole centre spacing are you going to use .197"=5mm
I've used 1" caps on 3/4" downcomers as it was a std size= cheaper and they work well....might be a cost advantage to be had here

cheers
bt1[/quote]

Yes, no blank on the top plate
I left the blank on the plates for the overflow from the cup to flow onto the plate and to keep the ratio around 9%
I didnt put the cups higher because I wanted it to flow more onto the plate rather than splash
It doesnt look like it in the JPG but in the DWG file there is lots of roon to sand down to 3.90 and to solder around the downcomer
I used a grid that gave me 9% for the area I had with 2mm holes. Spacing between the holes centre to centre is 5mm left to right and 7.5mm top to bottom
I just happen to have a bunch of that size cap here so free is a good choice!!!

[bt1]

Yes, no blank on the top plate

In which case should have shown both templates

I left the blank on the plates for the overflow from the cup to flow onto the plate and to keep the ratio around 9%

No advantage here... drill it

I didnt put the cups higher because I wanted it to flow more onto the plate rather than splash

Make absolutely no difference

I used a grid that gave me 9% for the area I had with 2mm holes. Spacing between the holes centre to centre is 5mm left to right and 7.5mm top to bottom

Normal is 5mm x 5mm.

Buy hey if you got all the answers before you posted why bother asking.

I'm done here
bt1

[CH3CH2OH]

Thanks bt1

If f I had all the answers before I posted, I wouldnt have posted asking for advice.

The waterjet guy isnt cheap so I was hoping for any consrtuctive advice before I shipped it off and spent a bunch of $$$. I really am a plated column newbie who doesnt want to pay someone to screw up an expensive sheet of 1/8 copper plate!!

I knew that the top plate was going to be being different but completely forgot until you mentioned it so THANK YOU

I appreciate knowing that I can drill under the cups without any negative effect.

I read that 8-9% is optimal. If I drill out the remaining cup area I am up to 10.2%, does that change the efficiency of the plate or increase the needed vapour flow to support the liquid on the plate or am I good to go ?? doesn't sound like much but it's about a 15% increase in the surface area of the holes.

Thanks for the advice

[Brendan]

Okay mate,

Here's the answers you may or may not want...

Yes your design will probably work okay...is it ideal or the most efficient? NO :naughty: I only mention this as you brought up efficiencies and optimal design...

I ran your numbers and came up with a plate hole coverage of 10.31%...I think that in your calculations, you weren't excluding the unused areas of the plate when working out the plate surface area. For example, all figures that you have read in professional writings are pertaining to the coverage of holes in the area where rising vapour meets liquid distillate...therefore you can discount your downcomer pipe area, as well as your blank area as liquid is just moving across it but not interacting...

By drilling out the holes in the extra area which was allocated for the 1 1/8", you are actually increasing the useable area of the plate, again where interaction occurs between vapour and distillate. Therefore you are effectively reducing your wet plate hole coverage to 10.22% by drilling that area. I calculated that this area was about 8.64% of the space of the plate, so I added 8.64% of 224 holes to come up with a total of 243 holes now by drilling that area, giving you a wet plate hole coverage of 10.22% of the 'new' area (obviously your calculation of the extra drilling accounted for more holes than what I did or it might have been the areas that you didn't exclude, doesn't matter). I don't see that making any difference, as bt1 said...

What I do see making a difference, is having that blank piece on your plate with no holes in it...if you want to look at efficiencies of the equipment, the whole goal of each plate is to bring as much liquid distillate into contact with rising vapour as possible...your design would limit this happening by up to 10% (8.64% in my calculations or 15% in yours), causing a fairly large inefficiency if you are going to the effort of designing it yourself and having it all custom manufactured :wtf:

Now you mentioned optimal design...I have also read quite a few technical articles that state the optimal design at 7-8% wet plate surface hole coverage for beverage production...so we'll meet in the middle and settle on 8% ;-)

If you're going to spend the $$$ on the waterjet cutting, here's my recommendation:

1.6mm holes (Or 1/16" = 1.59mm), in a 5mm grid pattern, with no blank space left for DC cup, just for the downcomer itself.

This will give you a wet plate surface hole coverage of about 8.1%...

Win/Win and you are using a tried and proven design that has been utilised by many of us here with impressive results :handgestures-thumbupleft:




p.s. If anybody would like to question the math, I am about to finish my engineering degree and would probably enjoy the discussion :-B :teasing-neener:

[bt1]

Nice post brendan,

side question I'd be on both platers closer to the 10.5% mark and can as a result throw some serious heat at it with out over powering it.

Is there any stated or tested numbers to relate to input recommendations?

Had really wanted to try 4mm x 4mm spacing on 2mm hole back drilled under plate with 3.5mm

bt1

[Brendan]

Nice post brendan,

side question I'd be on both platers closer to the 10.5% mark and can as a result throw some serious heat at it with out over powering it.

Is there any stated or tested numbers to relate to input recommendations?

Had really wanted to try 4mm x 4mm spacing on 2mm hole back drilled under plate with 3.5mm

bt1

I hear what you're saying about going to 10% to be able to throw power at it...

I don't have any evidence to support this, but just from what i've read from the ADI (American Distilling Institute), they seem to recommend not exceedong 10%, with 7-8% being optimal? :think: (Not sure if this had been quantified in terms of taste tests or what?)

The fuel/oil industry is another kettle of fish, where it's not about the flavour, just how far they can push their equipment to achieve what they need at the fastest takeoff rate...

Experiments are always useful to the rest of us, I just wasn't going to experiment with something like this before I had my first bubbler built, so I went with Mac's recommendation and a proven design that meets the suggestions i'd read in professional circles...