Adjustable Version and High heat load Version
http://www.blairwing.com/images/cascade.jpg
Capillary Tube Version
http://www.blairwing.com/images/mini.jpg
The infamous tristage
http://www.xtremesystems.org/forums/...id=27885&stc=1
Printable View
Adjustable Version and High heat load Version
http://www.blairwing.com/images/cascade.jpg
Capillary Tube Version
http://www.blairwing.com/images/mini.jpg
The infamous tristage
http://www.xtremesystems.org/forums/...id=27885&stc=1
nice pics chilly!
Retawi@cox.net my addy.... got anything you need... working ona website
Nice :) Could you lable the second one with all the parts though?
If you look at the first picture you can lurk it out what components the second cascade uses. If you don't know what those parts are you obviously shouldn't be into cascades. (bad english)
I'm to lazy :p:
Wth is a subcooler?
A subcooler is an HX used for lowering the temperature of the liquidline and raising the temperature of the suctionline in other words cooling the superheated gas/liquid in the liquid line..
Used to make the system more effecient.
I edited the posts for the desuperheater that is actually a device that is connect after the compressor to desuperheat the discharge gas from the compressor..
I drew these in autocad and colored them in photoshop..Quote:
Originally posted by blinky
nice pics chilly!
What you are describing is a subcooler. A desuperheater lowers superheat, which this does not. This in fact adds superheat to the suction vapor. The vapor/liquid mixture in the liquid line is subcooled, not superheated.Quote:
Originally posted by chilly1
A subcooler is an HX used for lowering the temperature of the liquidline and raising the temperature of the suctionline in other words cooling the superheated gas/liquid in the liquid line..
Used to make the system more effecient.
Thx Gary missed the error...
you guys 0 \/\/ /\/.
I think hes half asleep when he writes these sometimes Gary.
Basicly a problem with "smoke" :)
?????
He's from the city that never sleeps. :DQuote:
I think hes half asleep when he writes these sometimes Gary.
I'm still trying to figure out what a CPEV is. As near as I can tell, it's an AEV.
Constant Pressure Expansion Valve Yes it is an Automatic Expansion Valve.
Berlin? :oQuote:
Originally posted by Gary Lloyd
He's from the city that never sleeps. :D
Isn't the CPEV on the evap modified ... seems I read that in a very early post. :)Quote:
Originally posted by chilly1
Constant Pressure Expansion Valve Yes it is an Automatic Expansion Valve.
Only the settings are changed the device remains the same... O teah the internal is set a little different I lower the sprinc tention a half anotch..Quote:
Originally posted by Hobocrow
Isn't the CPEV on the evap modified ... seems I read that in a very early post. :)
Ya the strangeness has something to do with all the flashing lights and noisy buzzers, I think. Either that or Fugger keeps him up all night wanting to see that Ultimate O/C. :)Quote:
He's from the city that never sleeps.
They say it's the heat ... working on rooftops for the last nine years in the summers and temps around 140 with the rubber of your sneakers melting away in two weeks or less...
If only we could all be so lucky... :( I feel for you guys down there.
140F... Do you guys get alot of blow offs from pressure reliefs or by passes opening up?
I'd be afraid to even carry around refrigerant jugs. I've seen an old boss of mine do that.. /rolls eyes.
Chilly1, hehe ... I just knew that cpev on the evap was tweaked! ;)
I used to be very afraid. The iside of the van parked could reach 150F But never a one... Some guys who over charge the recovery tanks get a blow off or two. and you hear of someone not tying their tank down and it blew in the truck but not much...Mostly wear out shoes and drink way too much water ten 2 liter bottles a day plus what I drink at home.. At a minimum... We get a hugh number of burned out condenser fan motors with this heat they operate about 10 degrees above their maximum temperature. Even the new R410 systems dont have trouble.. The head is a little high at 550 psi discharge, but it appears to work ok.. So this is for all the worriers about cascades out there the cascade systems we build the head pressure seldom exceeds 300psi...Quote:
Originally posted by Redwolf
If only we could all be so lucky... :( I feel for you guys down there.
140F... Do you guys get alot of blow offs from pressure reliefs or by passes opening up?
I'd be afraid to even carry around refrigerant jugs. I've seen an old boss of mine do that.. /rolls eyes.
Nice, so with this system you can run 24/7 at around -50 and them drop it to -100 for benchmarking?
:slobber:
Not really if you build a chiler that is an option. with phase change a Temp range of -70 to -100 is possiable. Fractional HP compressors don't have unloaders..
Ok, but is -70 ok to run 24/7 and safe
keep it on ice for life!
Moisture is you enemy. Insulate,insulate,insulate and when your done insulate more...
chilly1 i wish you lived close so we could turn my prommy into a mod'd monster
hey Chilly,
Why you dont name each parts in those pics? That whould be great...
I think it is obvious skate2snow ;) get a cataglogue from ur nearest refrigeration specialist and everything will be catagorised in there.
He draw it to explain people, if people didnt understand how to loop a cascade, they probably dont know what each parts are...
Don't see why any temperature is great as long as the insulation is goodenough to keep the moisture from condensing on the components.
What is a TXV and how is it different form a cap tube?
I work at an automotive garage and we use soemthing called an orafice tube thats only about 2 inches long, is the TXV similar to that?
No a txv is what is on the higher end auto's Some use an expansion block, like all things automotive they rename it change the fittings to something no one else has and charge fifteen times the cost. The oriface tube is a fixed metering device that also includes a debris screen, this is simmilar in action to a capillary tube, theere is also an after market expansion tube that will meter the flow of refrigerant depending upon the entering temperature, so it will restrict the flow the hotter the entering refrigerant is. I had a 69 Mecury Montery 429 2brl, it had an R-12 AC with a 3 ton TXV The sensing bulb strapes on the suction line exiting the evap. The bulb senses the line temperature and restricts the flow of refrigerant if it gets too cold but this is depending on pressure.
Whats too cold? IS their anything where the user adjusts it, or does it just know?Quote:
The sensing bulb strapes on the suction line exiting the evap. The bulb senses the line temperature and restricts the flow of refrigerant if it gets too cold but this is depending on pressure.
also
is your website up? you seem very knowlegable and willing to help others understand, just wondering if it is up if their are any guides or nething.Quote:
Retawi@cox.net my addy.... got anything you need... working ona website
Thanks in advance.
Well the drawings are a good start and if you have questions PM me. Or email me and I will help you build your own. You can set the superheat with the TXV.
Three stage...
hmmm guess that answers my question about a reciever when using a CPEV....
Only need a very small reciever too large and the system volume of high pressure gas will be too high.
Why arent oil seperators used on the first stage of these systems, or on single stage systems? Is it just a matter of cost? Wouldnt the condenser and hx be more efficient if oil was seperated in the first stage, or is there a performance hit by adding one?
Regards
John.
At higher than -50 temperatures the oil returns well enough and if you have oil that will remain miscible to -100 while remaining viscous enough to lubricate the compressor then for systems within those temperatures then you would not need an oil separator. Although you would gain from the use of an oil separator on the single stage compressor it would be only 1 to 2 degrees at most. The addition of oil solvents with vapor pressures higher than the suction pressure is sometimes used to facilitate the return of oil in cases where there is no oil separator and where a small amount of oil may bypass the oil separator.
I think I understand that, are you saying there would be a small gain, because heat transfer would be better at the condensor and hx as the oil wouldnt act as a barrier to heat transfer between the refrigerant and copper transfer vessel. Also are you saying that there is no disadvantage?
Regards
John.
There is a little disadvantage when the float lets the oil into the compressor, but not much other than the additional cost of construction.
Is an interstage HX the same as a shell and tube HX, or are they different. Also what does the reciever in picture 1 do? Is it mjust a holding tank?
Same, There are two recievers they store the liquid that has comndensed in the condensers but hasn't moved on to the metering device.
Is that like what an accumulator does with gas, or is that not what an accumulator does?
No an accumulator is where the liquid that did not boil off in the evaporator is trapped.
Ahh, ok, so is an accumulator or a reciever essentally a tank, or are their more parts to them?
An accumulator has a u shaped pipe in it with a very small hole in the bottom for oil pickup. A reciever also has a dip tube in the bottom of the tank so the oil will go out with the liquid refrigerant.
If you have an oil separator in your system do thses still trap oil? I thought an oil separator separated it all and sent it back to the compressor?
Some oil still circulates in the system. And you would not want that to stay in the accumulator.
Why is the reciever for the first stage so much bigger than the one for the second and third stages?
In the first stage we need more gas becauste a small fluxuation in the third translates to a larger in the first. Also we need to minimize the total system charge in the second and third stages.
how many inches of 1"" pipe would you reccomend for the recieveer on the low side?Quote:
Originally posted by chilly1
Only need a very small reciever too large and the system volume of high pressure gas will be too high.
I use a 1.5 inch OD pipe and two pipe caps the pipe is 3 inches tall and the outlet is at the 1.5 inch level.
i really want to learn all this stuff about what each part is and does etc and how to build one, are there any good websites or documents explaining it all? or would it be best to just keep poping in and out of here and learn things over time?
Read the stickies, there are links there on where to go to learn more. Buy Gary's book.
talking abount garry
he's not around as much laterly has anyone heard form him?
hes missing all the cold action here
Gary is very busy at the moment. I got the impression hes got some personal stuff to take care off.
But he said he'd be back as soon as he could.
what gases could be used in a cascade low stage that dont require the use of high pressure cut off's?
Non that are worth the effert of making a cascade.
what about r507 and r404a for learning
then maybe later the good stuff.
what safety devices are needed in a cascade
pics please someone and/or a drawing
The infamous three stager......
Why you deleted the labels??Could you pls put lebels on the tristge???Pleeeeeease??
Question: Where can I buy Gary's book? and What is it called? Thx.
Titled tristage with additions.
http://www.xtremesystems.org/forums/...chmentid=22195
:slobber: :cool:Quote:
Originally Posted by chilly1
Thank you, Chilly1. It looks awesome. :slobber: :cool:
I think I get this now. and again, good job!!
these are gary's books: https://www.merchantamerica.com/tmethod/Quote:
Originally Posted by shadowing
Do we need to put some more oil in the system, or the only needed is the one inside compressors?
For a starter, in cascades, what gases can we use in first place to test our work, and what temps can we anchieve with them?
Do we really need an accumulator, or can we do a coil (what size +-?) with copper tube instead? (sorry if this is explained earlier, but I can't understand somethings)
Do we must insulate accumulators and oil separators?
Best regards!
suctions hx are essentialy?
I don't think so, but they improve the subcooling :)
Another question, what is the minimal compressor power for a cascade ? I was planning to make something out of two 1/3HP compressor, but I don't know if it will be enough to cool a gpu ;)
In cascades I think they are..
HX=Heat Exchange?
Also instead of using an accumulator, to boil off any remaining liquid in the suction line returning to the compressor u can wrap some copper tubing tightly around the compressor's shell to help cool it without having to worry about it sluging liquid.
Short answer is YES, but there are other considerations. Usually the tubing wrapped around the compressor is cooled by the gas adn does add load to the system.Quote:
Originally Posted by _HL4E_HalfLife_
Hi!
Could you tell me if are those Red marked right? :)
http://img147.imageshack.us/img147/9374/mini7xa.jpg
Thx
they are;)
Can i use 1/2" outter and 1/4" inner for the cascade HX? How long should it be?
you can, but you might use 5/8(outer) and 2X 3/16(inner).
more mass and surface, between 3-4meter it's fine
Does 2,90m of 0.031(0,8mm) Cap looks fair enough for R404a @ 1st Stage?
What about 2nd Stage, how long should it be?
Hm, I`m prefering ~ 2,3-2,4m of 0,8mm cap tube for 1 stage, and ~ 2,6 for 2 stage.
that cap configuration looks like for lots of capacity!?Quote:
Originally Posted by LukeXE
Yeap, that`s right...you should use shorter cap tube for I stage, because it must hold big load. I think that 2,9m is too much, as I said 2,3-2,4m or maybe 2,5m for I stage should be better :)
What gas do you wanna use for II stage, r1150 or co2 ?
i was thinking 1st, for tests CO2, them with more experience R1150
If I have to use diferent compressors, what stage should i use the most powerfull?
i think second..Quote:
Originally Posted by sl4ck
think about holding load, condensing r1150 is such a quiet big load for I stage, plus heatload from evap. You should use most powerfull compressor on I stage, to hold loaded II stage well.Quote:
Originally Posted by sl4ck
Yeah, you could use most powerfull com on 2 stage, but what you will do when I stage comp will have problems with holding load ? :)
Nice thinking LukeXE ;)
What about CO2 static and running highside pressures? CO2 is most less dangerous then R1150, rigtht?
If you use expansion tank (you should of course), then I think that static pressure won`t be higher than 10bar, highside pressure is limited to amount of gas in the system, so nobody probably won`t know answer for that question, but try to keep it under 15 bar.
CO2 is less dangerous than r1150, that`s right. For example, bottle with CO2 usually has CO2 at 40bar pressure, however R1150 is under ~80bar pressure :D
BTW, remember to use cut-off switch and high pressure relief valve for safety
I know expansion tank let us have more refrigerant in the system with less pressures, but if i don´t use one for now, at the beginning, should should the static pressures the same?Quote:
Originally Posted by LukeXE
I sent chilly1 a PM about using his drawing for something I am writing but I'm not getting a reply. Is it generally accepted that these drawings can be copied and used elsewhere with recognition? I don't want to step on any toes but I can't draw for a damn either and his designs are amazing.
as you will know reggie has been going through a tough time recently. I suggest you do NOT use his designs outside the forum, as they ARE copyrighted, and his interlectual property. You may want to PM fugger about them, as they are also copyrighted to XS, and fugger is in direct contact with reggie.
The actual drawings, i.e. graphics are copyright, however the detail is standard cascade design. So you will need to use your own graphic objects.
Regards
John.
K guys, thanks for the quick response. Time to look over a few various designs and whip out some MS Paint skills.
nice drawings:)
Oh, and if you label everything and not include cutoffs in the drawing someone will use them as a guide and not include them and it might explode
[ wow, starting to point out Wdrzal usually would]
and can i show my mad paint skills [i already modified a auto drawing but left the copywrights on and havent shown anyone {yet} and will delete the drawings if i can't use them.]
Heh, the drawings on my website are just for comparisons sake. If someone can get a system to work following those drawings then I'd be amazed. Those are there for just comparisons sake.
hey chilly could you please label this one for me would help alot
chilly is not around... Sorry mate. look at his last post...:shakes:Quote:
Originally Posted by ruffus
I'll label it, two minutes.
http://img223.imageshack.us/img223/6554/cascadehy7.jpg
There ya go, I'd drop the economizer on both stages, and the "receiver" post HX on the second stage.