JAn is building an autocascade

[jan]

I want to build a autocascade for the xtreme autocascade contest.

This are the parts i've build / collected so far. I'll start building the cascade when I get the missing parts. -> co2 and some copper tube.


This is the interstage hx. I hope this one will do the job.

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/hx1.jpg

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/hx2.jpg

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/hx3.jpg

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/hx4.jpg

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/hx5.jpg


This is the expansion tank I wanted to use in my regular cascade. I'll modify it so I can use it as a phase seperator.


http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/expt.jpg


I think I'll use the smaller condenser first. If its to weak I'll use the right one.


http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/cond.jpg


L'Unite AC compressor. 1HP.


http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/compr.jpg


Low and highstage gauges.


http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/gauges.jpg


The evap I've done. I don't like it and I think I'll do a new one. Maybe I can machine one at work.


http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/evap.jpg



I'll use cap tube ( 0.8 mm ) for metering device. Are 10 feet (3m) a good start for second stage?


Today I bought a 6kg bottle of CO2. Should be here next week.

[HawainPanda]

hmmm..the block seems to have really shallow channels...why don't u just make it deeper? itll do the job well im sure
nice hx! good luck!

[Tonic]

So, will you use capillary tube for interstage HX?

Will you use on first stage R22, or R290?

How did you make this spiral inside HX? Is it a 8mm OD tube?

[reject]

yes 3m .8mm captube is standard for cascade
defiantely try to make a different block
i like your HX what is that gold stuff is it ducktape? lol
good work

[cold_ice]

Looks good, but whats the use of this copper coil inside the hx?

[jan]

yes 3m .8mm captube is standard for cascade
defiantely try to make a different block
i like your HX what is that gold stuff is it ducktape? lol
good work

which gold stuff?
:confused:


as for the hx:

I added the ribbon to increase surface. It should add some turbulences. Dunno if it helps.

I got the main idea from chilly.

The HX is a 2 inch dia pipe with a spiral of copper inside for surface area adn the outside is 1/4 inch pipe for condensers...
Probably 2 ft of 2 inch and 2 50 inch pieces of 1/4 inch tube.
http://www.blairwing.com/images/2second1first.jpg

Because I've got only one second stage in this autocascade I thought the condenser would be cooled better if its inside the shell.

I used 4 m of 1/4" pipe for condenser. The shell is 45cm long. 50mm id.

[berkut]

VERY nice HX, i love it. Looks like a winner !

The smaller condenser should be enough, save the big one for a cascade :D

[Scout255]

Beautiful HX design, the best i've seen yet!

[kayl]

wow thats a big compressor, got to love those french compressers.
man i love your hx. it looks just like myone i made, i bent min around a shovel handle
its gonna be a killer autocascade there

[jan]

Thank you. Its nice that you like the hx. :)

This is the drawing which I am using as reference.

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/autocascadeB.jpg


When it is finished it should look like this:

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/auto1.jpg


It is not very big which is a big Pro :) The case to the left is for my single stage dd system. Its as big as a mach...

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/auto2.jpg


Here the setup of the autocascade:

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/autocascade.jpg

1. Both gases get compressed by the compressor
2. Both gases enter the condenser / phase seperator. The R290 is beeing condensed while the CO2 (gas) gets seperated from it.
3. The liquid R290 exits the condenser / phase seperator
3'. The CO2 (gas) is leaving the phase seperator and enters the interstage hx at 4'
4. R290 gets through metering device and evaporates inside interstage hx. It cools the CO2 so the CO2 can condense
5. R290 (vapor) gets through suction line back to compressor
5'. The condensed CO2 gets through the second stage metering device and evaporates in the evaporator ( 6 ). Then it gets back through suction line to compressor.


This is the condenser / phase seperator combination I've build today.

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/ps1.jpg
http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/ps2.jpg
http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/ps3.jpg
http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/ps4.jpg

[f00t]

very very nice. i can tell that its gonna be one of the neatest systems around when its done

[berkut]

place the CO2 filter before the hX. Filters dont work ok when they are cold.

[jan]

place the CO2 filter before the hX. Filters dont work ok when they are cold.

Thanks for the tip. I didn't know that. :) I'll change it.

[Tonic]

Flip filters by 45* degrees and add two service valves, one on CO2 and R290 line
(then you should drop add one of two gases)

[reject]

uh, i think i meant the ribbon you mentioned. was up late last night :)

[jan]

Today I did some piping. Mostly the suction line. I hope that I can finish the piping tomorrow. The regulator for the co2 bottle should arrive within the next two days. :)

At the moment I've installed a chilly1 evaporator. This is just for testing as I haven't done a diy one yet.

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/co2.JPG
http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/part1.JPG
http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/part2.JPG

[koensa]

nice compressor

nice system

nice builder

:toast:

[f00t]

mightwanna take that insulation off before you braze the rest together. i speak from exerience, of course ;)

[kayl]

looking good
i assume that bottle in that last pic was co2, what size and grade(type of co2) is it.
i like the gauges that you attached
are you going to use shadier valves for the other two points where you will check pressure or install permanent ones?

[jan]

looking good
i assume that bottle in that last pic was co2, what size and grade(type of co2) is it.


Yes it is co2. Its a 6kg bottle. Duno which grade it is. It can be used for foods. It was the only co2 I could get.

[zytrahus]

Hi, sounds good.

what kind of system do you use to join the gauge to the lines ? seems to be a screwed system ?

[jan]

They a connected via flare nuts.

but at the moment i am going crazy :( The system was finished and leakfree but the second stage cap tube was clogged. I've fixed this but now i have a leak and can not find it :(

[Epsilon]

That's the worst thing that can happen :(

The first thing i would check, is the HX :)

[jan]

Yeah, I'll check each joint this afternoon. :(

But I think it is the evaporator or the hose. This are the only two things I changed. Before I changed them the whole system was leak free. I think I'll rebraze the evap first.

[berkut]

how do you test for leaks ?

[jan]

I put pressure on the system. (this time i used co2 -> no nitrogen at the moment)
soapy water on the brazing joints. the evap i put into water.

how much pressure should i put on the system? 10bar?

[berkut]

i test mine at 20 as its the highest it will ever see

are you sure this is a leak, not oil absorbing the gas ?

[jan]

Yes it is a leak. But i think I've found it. When I put the evap into water at the bottom joint are very little bubbles. It was hard to see them.

I will fix this. The other joints on the system seemed to be ok. :)

[jan]

finaly i have a diy evap ready. today i brazed it in. at the moment i am evacuating the autocascade.

The evaporator:

it's 40*40. channels are 10 deep. a baseplate of 5 is left. the top is 5 thick.

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/evap0.jpg

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/evap2.jpg

the final autocascade (not insulated yet):

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/finish.jpg

http://www.mitglied.lycos.de/kryotech/Bilder/autocascade/finish2.jpg

[kayl]

very nice jan.
ya almost finished
how will you be attaching you refrigerant gauges to the co2 regulator??

[bh2k]

I gotta finish mine soo bah, no brazing rods and I need a tourch that doesn't give me 10 mins of brazing time ;)

[total_assault]

I gotta finish mine soo bah, no brazing rods and I need a tourch that doesn't give me 10 mins of brazing time ;)
I use a propane torch with a cable adaptor to fit my huge grill tank (used it for approx. 7 hours so far and it still seems full), I use Harris O braze, with my bernzomatic torch all the way up it works fine.

[runmc]

It is looking very professional Jan :) I think I'll pattern my HX after yours since berkut won't let me see his. :(

WE HATE LEAKS :mad: :mad: :mad: :mad: I spent my entire weekend chasing two leaks. Good luck finding your ;)

[berkut]

Yeah right i wont let you see mine :P And whats this :D http://www.teampuss.com/berkut/AUTOCASCADE/2/

A bird ? :]

[Epsilon]

Hx ? :)

edit:

If i may guess,

The innertube will be brased shut (to decrease volume).

[bh2k]

I use a propane torch with a cable adaptor to fit my huge grill tank (used it for approx. 7 hours so far and it still seems full), I use Harris O braze, with my bernzomatic torch all the way up it works fine.

How are the heatup times on a tourch like that? I was thinking of just getting a map gas tourch because I hear those last a long time or maybe an oxy/acy tourch.

[jan]

how will you be attaching you refrigerant gauges to the co2 regulator??



http://mitglied.lycos.de/kryotech/Bilder/autocascade/co2c.jpg

[berkut]

Hx ? :)

edit:

If i may guess,

The innertube will be brased shut (to decrease volume).

the inner tube is the sucktion line from the co2 evaporator

[i_like_penguins]

I love the zip ties. Those things are almost better than duct tape. The cascade is looking good too.

[kayl]

k thanxs for that, thats the bit that was worrying me.

[Epsilon]

the inner tube is the sucktion line from the co2 evaporator

Nice idea :)

[gkiing]

No oil separator? Is the red pipe an oil sep or phase sep?

[gkiing]

Yeah right i wont let you see mine :P And whats this :D http://www.teampuss.com/berkut/AUTOCASCADE/2/

A bird ? :]

Is that your magic device that fixes the issues with CO2?

[Blergo]

Is that your magic device that fixes the issues with CO2?

didnt berkut say that he had to mix R22 and R290 in with the CO2 and put the evap lower than the cascade to stop the CO2 solidifying? im sure he said that somewhere. mabey im just going crazy :rolleyes:

[Russell_hq]

yeah, he said that in his -100ºC thread.

http://www.xtremesystems.org/forums/showthread.php?t=49880&page=1