2-Stages Cascade @-98.5°C

[before]

Specs:
2 * 1HP Rotary Compressor
First stage refrigerant: R290
Second stage refrigerant: R170
Evaporator temp: -98.5°C unloaded

So here are the pics of my cascade...

http://www.beforeoverclock.com/images/cascade1.jpg
http://www.beforeoverclock.com/images/cascade2.jpg
http://www.beforeoverclock.com/images/cascade3.jpg

Who's that guy? Looks like me :D

http://www.beforeoverclock.com/images/IMGP1504.jpg
http://www.beforeoverclock.com/images/IMGP1510.jpg
http://www.beforeoverclock.com/images/IMGP1511.jpg
http://www.beforeoverclock.com/images/IMGP1513.jpg

Final temp (not -100, but close to... :p )
http://www.beforeoverclock.com/images/IMGP1509.jpg

[Electron Chaser]

Whoa!!! some very nice temps with only a 2 stage cascade. You can't sqeeze out another 1.5 C somewhere.

[greenmaji]

sure theres got to be one pipe in there thats below ambient he could insulate ;) :p

You sure did take a break from posting to bring out your cascade master skillz :D

Its SICK! :D

[Gautam]

Excellent! I love the 2x1hp's. Can't you stick some ice on the condensor or something just for the sake of hitting the big -100? :p

[Ad Rock]

oooooooh looks very nice, it seems pretty small too which I like a lot. What are your load temps looking like?

How long did it take you to build?

Also there has to be someplace on the unit you can maybe ever "cheat" to get to the very special number of -100c :D.

[before]

Thx! :)

The cascade was initially prepared by Pgeo, and then modded by Luigi and me during few hours. :)

CPU idle temp was -61°C with an FX-55 3.7GHz@1.68V ; don't know about load one yet. I guess about something like -47°C... :rolleyes:

I've thought about using the liquid chiller to cool down the condenser in order to hit -100°C ... :p

[bazx]

nice one

got any diagrams of the set up

[dz_jad]

**me runs out to find out what a cascade is**

:drool:

My premature guess is something like 2 phase changes in series....

[Ad Rock]

nice one

got any diagrams of the set up

I would love to see any plans/diagrams you have as well.

[before]

I don't have some; but I could draw something if you want :p

[jinu117]

Good stuff.... Just be careful... :) Ethane isn't too cool to play with (pun intended).
Got any high pressure cut off?

[before]

Thx; yeah, you're right, ethane isn't safe at all. I would have prefer another refrigerant, but actually R290 is cheap and BTW was the only one we had at Luigi's home the day we charged the first stage.

What do you mean? A kind of CPEV or something?

[XeonStrikeForce]

Uhm NO, It is a unit that will electricly shut down the system should pressur exceed a safe limit, and other wise usless as pressure will continue to rais dangerusly, they MUST be used in tandem with a High pressure relief velve Say 400PSI cut out and a 500 or 600 PSI relief, or less if it makes you feel safer.

Basicly it ensures you and your system dont go BOOM with each other

[-aDaM^]

wow very nice, would be cool to see -100*C :D

[Dan0512]

WoW what a handsome guy!

Anyway, nice setup!

dan

[greenmaji]

What is your static preasure on the high side? And what was the room temperature when it was measured?

@dz_jad basicly yes.

[speed bump]

Good stuff.... Just be careful... :) Ethane isn't too cool to play with (pun intended).
Got any high pressure cut off?

Actually no one I have ever seen build a phase change system has put a high pressure cut off valve into there system. Why the only place you can possibly need it is during charging and that is done via charging to a certain PSI so its alot less of a problem than it appears to be.

Nice cascade, although its been a while since I have seen r170 used in a cascade nice to know there are still some inexpsively gassed cascades out there.

[jinu117]

Actually no one I have ever seen build a phase change system has put a high pressure cut off valve into there system. Why the only place you can possibly need it is during charging and that is done via charging to a certain PSI so its alot less of a problem than it appears to be.

Nice cascade, although its been a while since I have seen r170 used in a cascade nice to know there are still some inexpsively gassed cascades out there.

For other gases, highpressure cut off might sound useless... but with somethign that can become explosive under high pressure... it is a MUST.
I will give you a scenario... on cascade, let's say his first stage for some reason stopped running... 2nd stage "condenser" gets warmer and warmer... next thing you know you have VERY high pressure of ethane sitting in 2nd stage. Pressure keeps rising and one of component in loop starts breaking... HIGHLY compressed gas gets into atmosphere with electric things all over including inside motor... Now do you see potential for exploding cascade?
Let's put it this way, I am building cascade now and however slim the chance is, I don't want to take it so getting R508 gas... Ethylene is about 21x cheaperthan R508 and might get better temperature by 5-10c... but safety is something not to be scoffed at.
As for no one uses one... I hope people are not selling these flammable gased units without high pressure cut off.... it could be as simple as fan failing to work that can cause mishaps.

[greenmaji]

I keep reading chilly1 say that all you need to do is to make the high side have enough capasity to keep the static charge low enough at the highest room temperature possible (done with expantion tanks and such).. But he also says to use a highpreassure cut off switch..

I'm sure Gary Lloyd would be going nuts right about now over this, I'm going to link you guys to his sticky about how dangerious a cascade can be mmmkay.. ;)

http://www.teampuss.com/forums/viewtopic.php?t=75
stimpit..
Cascades Can Kill You:
There are cascade freezers in common use in labs and blood banks all over the world. Are the people who works in these labs in danger? No. Why? Because those freezers were designed, built, and serviced by people who know what they are doing.

Do it right, and it is no more dangerous than any other refrigeration system. (Okay, maybe a little more dangerous).

Do it wrong and it is a bomb.

I see WAY too many totally clueless noobs talking about building cascade systems. This scares the hell out of me. Someone is going to die.

Frankly, I am torn between teaching you and discouraging you.
he reponded to questions at the thread linked..

@jinu117.. Your cascade at XS looks KILLER man..

[XeonStrikeForce]

I read about the idiots that don't use pressur cut outs or safety switches and all I think of is "Futur corner bait" and as harsh as it is, this IS the finite reality of it. I've seen what the human body looks like after an explosion, aside from the smell its easy to remember how weird some one looks with chunks and stufe missing, the question is do you want to experiance this? if your sane and compitant mentaly no, you would not, they aren't that expensive either.

DO IT RIGHT OR NOT AT ALL! IT WILL END YOUR LIFE IF IT FAILS AS BAD AS IT CAN!

[XeonStrikeForce]

FYI: You don't need heat to throw shrapnel, a static pressure burst is just as deadly, just depends where the shrapnel tears through you! and at the volocity it will be traveling at it needn't be big.