nice :) same connection as an ethylene bottle?
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nice :) same connection as an ethylene bottle?
Yes same connection. Seems that the bottle was used for hydrogen before, because on the valve there is written hydrogen :D
Its just good practice and freak stuff does happen. Plus I think that metal cap could be easily broke off with a nice fall.Quote:
Originally Posted by cold_ice
the metal cap is strong trust me :) its made for it ;)
and i don't think he is going to fly with the bottle :D
Then I fall back on good practice :D
those metal caps are screwed on. they don't just break off, it's very strong. my gas supplier has lot's off bottles standing like that as long as the cap is screwed on.
so you just gonna use the regulator that you got for the 1150. or just buy another one, their pritty easy to get:toast:Quote:
Originally Posted by cold_ice
do you have methane outlets inside your house? ;)
Metal cap dosnt come off? have any of you guys EVER been to a REAL industry? They come off just fine, just has to land right, which seems to be the way they like to land. The metal cap is to stop the velve from geting dirty or damaged, not to save it from a high fall (From standing to landing is considerd high), At camp you'd get slaped and have to buy every one on site a 6pac for leaving a cylinder like that! same for diving cylinders or propane tanks.
Ask your self, is such a simple task worth your life? if the answers No, then take the time to lay it down or chain it!
FYI: Your suplier is an idiot at best, but definatly a dangerus one, I'd report him, the caps are not to be relied on totaly, they are but one step in a stage of safety mechanisms, they only work when the rest do.
Maybe the bottles in the US are different, but there is no way that the cap will fall off when the bottle topple down. The cap must be screwed on when the bottle is not in use, or when you transport it.
At every gas supplier the bottles are stored with caps on but with no further protection.
But lets move to the topic...
Today I almost completed the third stage, will do the last brazing joints tomorrow.
http://www.extremecooling.net/random.../4stage/92.jpg
http://www.extremecooling.net/random.../4stage/93.jpg
http://www.extremecooling.net/random.../4stage/94.jpg
http://www.extremecooling.net/random.../4stage/95.jpg
http://www.extremecooling.net/random.../4stage/96.jpg
http://www.extremecooling.net/random.../4stage/97.jpg
http://www.extremecooling.net/random.../4stage/99.jpg
it is the jungle here :D
3rd stage complete. When there are no leaks charging will be tomorrow.
http://www.extremecooling.net/random...4stage/100.jpg
http://www.extremecooling.net/random...4stage/101.jpg
http://www.extremecooling.net/random...4stage/102.jpg
http://www.extremecooling.net/random...4stage/103.jpg
http://www.extremecooling.net/random...4stage/104.jpg
http://www.extremecooling.net/random...4stage/105.jpg
http://www.extremecooling.net/random...4stage/106.jpg
http://www.extremecooling.net/random...4stage/107.jpg
http://www.extremecooling.net/random...4stage/108.jpg
http://www.extremecooling.net/random...4stage/109.jpg
http://www.extremecooling.net/random...4stage/110.jpg
http://www.extremecooling.net/random...4stage/111.jpg
Waiting 4 the day that beast fired up . Keep it up Man :D
awesome!!!
i wanna see it working!! :D
I hope for you, you don't have leaks! manouvering your torch in there will be a problem I think :D
No the botles are the same, but the safety laws are very strict, and for good reason. But in any case the system is looking very nice, any schematics of it drawen up?
Hey sorry for the really noobish question but still trying to learn all this stuff.
What are the big insulated boxes and what is their purpose in the system.
Also (more noob), those black clinders are oil seperators???
Jesus im dumb :woot: :banana:
they are plate HXQuote:
Originally Posted by kommando
i think it s expansion tank
Inteligents is realitive to your environment, If you where a farmer and you knew squate about dirt then yes, you'd be pretty stupid as you have to know about dirt to be a good farmer! But if you're a farmer that knows squate about computers then no, of course your not dumb, you're simply out side of your field.Quote:
Originally Posted by kommando
So again you are not dumb, simply in unfamiliar territory, with your brain opperating quite well, becuase if it wasn't you wouldn't have asked ;)
Heat Exchangers and as for the tanks, they do indeed apear to be for expansion perposes.
Ah okay, thought it was something along those lines.Quote:
Originally Posted by Xeon th MG Pony
Great project though, will be watching so I can pick up a few things so I have knowledge when I get started with this stuff.
skirms_fr and Xeon... are right.
Yes I really hope there are no leaks, will be a PITA to fix it!
wooo thats really starting to get big... if it were me id have trouble remembering whats what.
see that guys, a releif valve :woot: :woot: :woot: that simple little device will keep a failure from occuring, as long as they are sized correctly of course.
Nice work :toast:
That truelly is xtreme :woot:
wdrzal is finally happy :) very wise cold_ice to put the valve on.
if that release valve is for flammable refrigerants make sure you have some airflow around the valve so the concentration of refrigerant is fast reduced to non-flammable. But seems to me like that won't be much of a problem in this case seeing the desuperheater near it.
what's the function of a releif valve?
I guess the relief valve is safetyfunction, to release pressure from the system.Quote:
Originally Posted by GuuZ
i like the way cold_ice has split the condenser to be 3 desuperheaters :D
I won't just release methane into the ambient now would it? But hoe else could it release pressure?Quote:
Originally Posted by Big SturL
it just releases refrigerant into the room, but that's a lot better then a pipe/weld break dumping everything at once into the room at very high pressure. Big boom/room gone. It's not really replacing a high pressure cut-off more an extra safety in case the pressure still rises after shut-down (which is pretty likely considering you'll have some liquid refrigerant left in the high side after shutdown.)Quote:
Originally Posted by GuuZ
methane is found in hyrdrocarbon fuels like oil,gas and coal and is naturally released into atmosphere and does not cause any problems except for the flammablity issue. There should be a tube to vent it away from any ignition sources.
but even chloroflorocarbons that destroy ozone are allowed to be released as a last resort safety measure, which a releif valve is. Its preferable to have a small relese than to blow up a building or kill someone.
how about short circuiting it with the low side? You don't have refrigerants in the room andyou don't need to refill after it happens but the pressure will get lower. (offcourse only when the compressor is already shut off by a high pressure cut off)
U_R, you mean something to electrically parralel to your compressor wirings, sort of a relais, when powered on it's closed and when powered off it's open? Sounds like sort of an electrical valve to me?
no just an release valve but it doesn't release into the atmosfere but into the low side (maybe expansion tank) of the system.
wouldn't that be about the same as a high pressure cut off?
No it would instantly equalize the pressures on trigger by directly creating a bridge from high side to low side.
fyi: Methane, you get lots of it when you eat cabage or beans !! no where near pur though.
Now the failur that can happen with that is if the system where over charged the pressure will still rise to a potentialy dangerus level, and you had beter be sure of your brazing skills!
why would you need a direct bridge from high side to low side? A high pressure cutoff should be enough too right? Or is it because pressure can rise faster than the cutoff can handle?
the cut off just stops the compressor, then pressures will still clime far faster then they can level out.
I'm going to get me coffe' my spelling is bad at the best of times, let alone first off in the morning! lol
lol 7 o'clock noon here =P
anyway, what we're looking for is a pressure triggered valve?
Idealy, but I supose you could use a electrical one, but you'd need a slightly complex method of electrical trigger.
Good that wdrzal is finally happy, now I have pressure releif valves and high pressure cut offs in all stages (except in the first). I think thats enough for safety components.
This unit will never see my flat, its only in the garage which is well vented.
The idea with the connection bezween high and low side is nice. But whit which valve that can be done? Don't know any for this purpose.
Maybe some sort of a check valve :confused: incorporated with the pressure relief valve.
Looking good cold_ice;)
cold ice do you have one on everystage except the first????
you have 3 lines of defense against failure,
first is the pressure switch that shut off the compressor, but if you have a blockage or overcharged or the switch fails or is set wrong you need another way to stop pressure rise. a pressure switch only shuts off the compressor and the compressor is not usually what causes pressure to build to failure.
second a compressor has a internal bypas that opens and lets pressure to low side , this was mention above as a idea but already exists. This usually works unless the system was serverly overcharged, which most systems are. When called to check a system that is not operating properly ,I've removed far more refrigerant than I have put in. like here on the forum most people think that either by using a bigger compressor or adding more refrigerant the system will work better.
Third the releif valve is a mechanical device that if all else fails it opens and lets out enough gas too lower the pressure to a safe level.
xeon it has nothing to do with how well you can braze, all conponates will fail at a certain point, .
the problem with a cascades is if ther is to much gas, once they are shut off,break or a blockage occures, they start to warm allowing the high pressure liquid to expand as it tuns back into a gas............ because you are using second,third , and forth stage gases, this expansion CAN NOT be STOPPED until all the liquid is gas , as liquid can not exist at ambiant temperatures, as 1st stage gases can.
any leaks found, cold_ice?
I know that wdrzal, but what will be the first to fail eh? I'll help ya out it will be the weakest componant which will naturaly be a bad joint, next it will be what ever is on your system that isn't rated at that opperating pressure (And even then the ratings are so conservitive you have a fairly high safety margine)
But I do agree non the less a proper machanicle reliefe valve is the only real safe option, very unlikely to fail, and will finitly drop pressure without dubt.
But the bypass idea would be worth a shot to avoid venting refrigerant, if it failed then the blow out valve triggers and all is peachy, we tried at least.
Agree? No?
first : a large diameter tube that is perfectly brazed or even the compressor encloser itself will probably fail before a small diameter tube that just has a defect. a severly bad joint will be found during leak testing,and visual inspection.
psi affects larger surrface more serverly.
second: as your idea of a internal bypass, if you read what i already said ALL compressors already have them.some use a poppit type that self resets and some compressures use a burst plate between the high and low sides, once triggered the compressor is junk in the latter..
I read your post, there is more safety in redundancy, and in the case we are talking about we can set it at the pressure we want rather then guessing at what the compressors may be.
that is one hell of a nice cascade, a real handywork,
All pressure releif valve come pre-set and should not be tampered with. they need to be sized for the psi at which they open and the BTU's they need to unload.
Hi Cold Ice, You want -160, is that C or F ?
Check out the Temprites at : http://www.temprite.com/main_catalog...y=288&item=965
Think out side the box... something like a mix in the R14 stage and a second separator after an added auxiliary condenser to trap the oil and the added high boiler. The oil will need to be miscible with the high boiler. Zerol would be a good choice for the oil. A cap tube could be used to control the feed of the high boiler back into the suction upstream of the auxiliary condenser. You could get some good suction cooling for the compressor and some precooling of the R-14 This would be sort of a hybrid of a cascade and an auto cascade. The high boiler, I'm not sure but my first thought is R-22. I need to think about what it might do when mixed with the R-14.
Another thought, R-14 will give you -120c with a 10 psi evap pressure. Try adding some argon to the R-14. This should lower the temp. but drive up the discharge pressure and temp. The added suction cooling provided by the high boiler will help overcome this.
Sounds wacked? I have systems that will do -170c with low loads. -135c with 2500 watts of heat load. Yes these are auto cascades.
Stay cool,
Wow, looks like a phase change god has just entered the forums...:worship:Quote:
Originally Posted by cryo-tek
wlcome to xs! :welcome:
EDIT: and what kind of autocascade do you have running with temps @-135C on a 2500Watt load??? What size compressor?
Are there any types of pressure refliefs that releive the pressure from highside into low side?
just a pressure cut-off and a solenoid valve parallel over the compressor...
what's a solenoid?
In our language we call it a "magneetventiel"Quote:
Originally Posted by GuuZ
ok, but what's the exact function of a solenoid valve in this case?
-160°C is my aim, I've done -115°C with a two stage cascade already. I got the Henry oilseparators rather cheap, this is why I used them. My first choice are Danfoss oilseparators, never tried a Temprite.Quote:
Originally Posted by cryo-tek
Do you have pictures of your autocascades? -135° with 2500w is crazy, must be a real big unit. What are you cooling with this monster?
I fired up the cascade yesterday (first three stages). But the first stage seems to have a problem, high side pressure is pretty high with R404a when all stages are on (23bar!). Temp isn't good either, about -35° HX-Out. I'm not really happy with it. Shortened the captube two times, still the same problem. Will shorten it today for another time, if this still doesn't work I will try a Danfoss TEV instead. The other two stages seem to work fine, but I can't tune them when the 1.stage isn't working correctly...
Saw some temps in the -130°C range with alot R1150 in the 3.stage, just a few squirts of R50 in it. It's awesome when the whole suction line back to the compressor "smokes" because of the cold temps.
I think chilly used temprite oil seps with R14 but they didn't work well enough either.
cold_ice: can you give more info about the first stage? condensor temperature, suction pressure and superheat ?
Top of condenser was warm/hot, bottom was ambient, discharge line was pretty hot. Suction pressure was 0,5-1bar, suction line was frosted back to the compressor until 3cm.
I know this is inaccurate, will note the exact temps and pressures today afternoon.
Also get another offer for R14, 1,2kg for 160€. 6kg for 500€ would be cheaper (per kilo) but 1,2kg should be enough for several cascades. Will order it.
are you working in a cryo cooler company?Quote:
Originally Posted by cryo-tek
do you have a recovery unit?that would be ideal when dealing witch such expensive gasesQuote:
Originally Posted by cold_ice
cold_ice, maybe You should try CPEV on first stage ??
A cpev on a first stage is a bad idea if you ask me. To much load changes.
TXV would be the best I think.
But I hadn't good results with valves in my previous units.
Quote:
Originally Posted by esdee
:stick:
R14 with a recovery:eek:
and like U_K saids, a 4stage with cpev on the first stage is asking for trouble
you guys seem like the mythbusters, you only want big boom! :lol:
btw cold_ice TXV's are sometimes hard to handle indeed but when they work it is ideal! Make sure the bulb is placed on a horizontal piece of piping and the let the pipe go upward after the bulb so the liquid wants to stay there. I think this will improve reaction time and prevent floodback most efficiently.
Plz explain why CPEV @ first Stage isn't a rly good idea! ^^ :)
because the first stage needs to transport VARIABLE loads:)
go figure, a cpev keeps the pressure CONSTANT ;)
Cold_Ice, Have you tried R-22 in your first stage? Another thought is to try adding some R123 along with the R-404a. The 123 will Reedley condense and reject lots of heat at the condenser. What can I say, I'm an auto cascade guy and I like to mix my gas.
When I start with a proto type I use 6 to 8 cap tubes to get to my expected flow. This gives me the ability to pinch closed some to adjust the flow on the fly.
The temprite 900 series are coalescing separators and should remove most of the oil. Are you putting the 4th stage oil separator someplace were the discharge gas has been cooled?
Do you have a drawing of your system?
I'm off to my mom's this weekend but when I get back I'll draw up something else you can play with. What gasses do you have? Do you have a spare compressor in the 1/20 hp low back range?
Stay well,
why try r22? R404a should work fine. why trow in r123? it isn't logical that it will reject heat at the condensor, it will probably vaporise in the compressor just adding extra heat to the condensor.
i know you can't recover r14 in it's original bottle. (cause you cant get it liquid again) but in several regular freon bottles... i do this all the time to save as much ethylane i canQuote:
Originally Posted by Jort
Ethylene? Lol... at least that is cheap gas that is natural forming for sure... Cheaper than most refrigerant out there anyway... :)
And here I am sitting wondering how can I recover r508 lol... good luck... maybe i need those 100lbs recovery cylinder instead of 30lbs ones here for some decent amount of recovery...
I can get R22, buts not allowed to use in new units here in Europe. I don't get the idea of using R22 instead of R507 but ok...
I don't have a drawing, but the circuit is nothing special. Almost the same as 2 stage cascade only with 4 stages.
Ethylene is not that cheap here, about 45$ for one kg.
Did some more testing today, shortened the captube down to the half (1,8m). It got a little bit better, but I'm not happy up to now. Maybe I'll replace the whole captube, or I will try a TEV.
Blending the methane with the ethylene is like a game, sometimes it droops very fast to the lowest temps, than it gets 5° warmer again. I this mix wouldn't hold load well, R14 is the better choice here for sure.
And maybe R23 in the second stage instead of the R1150 would be better. This gets expensive...
Some pics:
http://www.extremecooling.net/random...4stage/112.jpg
http://www.extremecooling.net/random...4stage/113.jpg
http://www.extremecooling.net/random...4stage/114.jpg
http://www.extremecooling.net/random...4stage/115.jpg
http://www.extremecooling.net/random...4stage/116.jpg
Pressure 1.stage
http://www.extremecooling.net/random...4stage/117.jpg
Pressure 2.stage
http://www.extremecooling.net/random...4stage/118.jpg
Pressure 3.stage
http://www.extremecooling.net/random...4stage/119.jpg
http://www.extremecooling.net/random...4stage/120.jpg
http://www.extremecooling.net/random...4stage/121.jpg
http://www.extremecooling.net/random...4stage/122.jpg
Here a little video: http://www.extremecooling.net/random...stage_test.mpg
Welcome to -100C club :P
Nice shooting there mate. Amazing setup. Don't you need to start worrying about co2 in the air and other such gases condensing onto your evap?
I can't wait to see the insulation.
i know it's rather cheap, and you need way to many bottles to recover a high pressure gas in air form, but i usually save small ammounts of ethylane that i need to release or charge the system while finetunning... nothing special but with so many tests i have made i guess i would have need twice the ammount of ethylane i have already consumedQuote:
Originally Posted by jinu117
@cold_ice
is it possible dat some R507 has leaked away and therefor is causing bad performance?
from the pictures and video it looks like you have pretty much floodback, I recommend you use a TXV for the high stage with a 01 orifice (I think), it will limit the floodback and your still able to give the stage some big loads.
and make sure that every piece of high side of stages 2,3 and 4 is insulated. I now see frozen driers and cappilair, in the drier and cappilair the liquid r1150/r14/r50 warms up and even boils. This isn't very good for performance and gives very inaccurate test results.
Offcourse the suctions also needs to be insulated before you can do some fine tuning but thats logical.
btw are the expansion tanks doing their jobs? normal static pressure?
@guuz, that isn't the problem
I will go for a TXV as you suggested. I think an internal equalized will do it. I look if I have a small receiver here, so that I can do this tomorrow.
I will insulate, just wanted to see some ice :D
Maybe I will go for ethane in the second stage, seems to be the best gas for this job. But it's expensive, so I don't know if I should take the R23 or ethane.
The expansion tanks are working fine, static pressure is ~10bar or below.
Definetly try out ethane. Its much easier to condense than ethylene and can actually be easier.
Changed the captube for a TEV today. Also added a receiver, sightglass and a new filter.
I only had time to do a short test, but the condensing pressure is alot lower than before. Should work fine.
http://www.extremecooling.net/random...4stage/124.jpg
http://www.extremecooling.net/random...4stage/125.jpg
http://www.extremecooling.net/random...4stage/126.jpg
http://www.extremecooling.net/random...4stage/127.jpg
http://www.extremecooling.net/random...4stage/128.jpg
http://www.extremecooling.net/random...4stage/129.jpg
nice rig.
nice!
i'd hate to see your power bill - keep it up :)
I wonder if in the end it can be converted to a 5 stage w/ nitrogen..
Holy Crap!!! :slobber:
This cascade deserve to have it own song...
"It's colder than ice..." :banana3:
n2 is liquid at -165°C at 10barQuote:
Originally Posted by n00b 0f l337
i think therefor he would have to change all the compressors to bigger ones...
danfoss sc21 is not bad, but for a 5 stager? (i would take a 400V rotary)
btw http://www.airliquide.com/en/busines...r_pressure.gif
wouldnt argon be the better choice for a fifth stage?
Quote:
Originally Posted by godmod
its only a 4 stage. (lol "only")
anyways, i feel like you should have tried replacing the cap tube before you got a tev, you may have just clogged it.
Yes but a TEV should work better. We will see.
I don't think that was the problem, although a cappilair can be used with some load changes I think the load change was to much. So at one point your flooding the compressor and with all the stages powerd up your almost starving the HX.Quote:
Originally Posted by Revv23
The TEV works very nice! The condensing pressure with load is normal now, 12-13bars. It works alot better than with the captube. Maybe I will get a TEV for the second stage too, for R23.
OMG its a monster
-100 club bugger that -150 club i reckon
Quote:
Originally Posted by Unknown_road
yeah i agree tev is better to use.
Watching this tread 4 quited a time now, realy awesom to see this monters taking shape.
Can someone tell me what is the lowest temp reached with phase change?
-165C ish by pc ice with a 3 stager n methane. Held no load thouhg.
:eek2:
That rocks. To bad it's that pricey to build
how are things going with the first 3 stages mr cold_ice ? all 3 stable now?
Today I rebuilt the second stage. I use a TEB2 for R23 in second stage, a receiver, a Danfoss sightglass and Castel filter. I hope I get the R23 and the R14 next week, both are ordered.
So gasses will be R507/R23/R14/R50
http://www.extremecooling.net/random...4stage/130.jpg
http://www.extremecooling.net/random...4stage/131.jpg
http://www.extremecooling.net/random...4stage/132.jpg
http://www.extremecooling.net/random...4stage/133.jpg
http://www.extremecooling.net/random...4stage/134.jpg
http://www.extremecooling.net/random...4stage/135.jpg
http://www.extremecooling.net/random...4stage/136.jpg
http://www.extremecooling.net/random...4stage/137.jpg
http://www.extremecooling.net/random...4stage/138.jpg
http://www.extremecooling.net/random...4stage/139.jpg
http://www.extremecooling.net/random...4stage/140.jpg
Started with 4th stage yesterday. The R23 should arrive on Thursday, hope the R14 this week too.
http://www.extremecooling.net/random...4stage/141.jpg
http://www.extremecooling.net/random...4stage/142.jpg
http://www.extremecooling.net/random...4stage/143.jpg
http://www.extremecooling.net/random...4stage/144.jpg
http://www.extremecooling.net/random...4stage/145.jpg
http://www.extremecooling.net/random...4stage/146.jpg
All I can say is that considering it's a 4 stage, things look very tidy.
I think we're all anxious to see this one all finished and charged, and it seems like you're getting closer to that goal, keep it up!
Will you be adding argon to the r14 for colder temps?