Cascade oil seperator

[n00b 0f l337]

If you put an oil seperator on the second stage with a packless valve, how often must you turn it to suck the oil back into the compressor?

[Jort]

put a sightglass in the circuit.

finished my cascade today.

http://www.belgium-coolingsolutions.be/Pics/Bench_cascade/DSC08631.JPG

http://www.belgium-coolingsolutions.be/Pics/Bench_cascade/DSC08490.JPG

just when its full i'll open it :) maybe 4-5 hours(sightglass isn't dry yet, going to do a full tripple vacuum tomorrow)

[n00b 0f l337]

Whoa I was just thinking that too! I didnt think of the wait till it fills though. Will the compressor operate just fine with a bunch of its oil sitting still?

[star882]

You might even set up something to optically sense the oil and open a solenoid valve.

[n00b 0f l337]

Well thats what float valves in oil seperators are good for. But if your just using a 10" tall 1" diameter tube with copper mesh in the top half, its a bit different.

[Revv23]

i think PC_ICE has his guys open her up every 2 hours or so...

[n00b 0f l337]

Can you open it while benching? I geuss its only a second or so?

[hatemi]

you can run it open all day long if you use captube to connect. It will lose you some capacity tough, but ueasually there is more than enough grunt left there with it open too.

The way I instructed the guy i sold my cascade was this:
Keep the oil valve open for a few minutes when you start the second stage, and open it few minutes before you stop. You can also keep it open all the time if the evap temp dosnt rise too much under load.

[n00b 0f l337]

I'll test that hatemi. Thanks for the advice. Now I just need to find something other than r744 (co2).

[kayl]

i normally leave mine open on pull down, wait til it hits -100c then shut it off.
Then open every hour or so if i remember for a min or so

If use a longer length of capillary line for oil feed will effect system less

[n00b 0f l337]

Like how much long and longer. 10 ft of .028? 20 ft?

[wdrzal]

too long and it will fill and you won't be able to empty it. There is no difintive answer,oil viscosity and the changes in pressure constantly alter the flow rate.

[n00b 0f l337]

So even with like 20 feet of .028 or something for oil seperation, why wouldnt the suction suck the oil out slowly?
Just to hard?
Ive got tons of capillary lines but no packless valves so I'm looking for a way to save money.
Starting my cascade soon (really soon, plotting on wood this weekend) and I've gotta roar up some money for safety devices (high pressure cut-off for the low stage) and a braided flex line.

[Tyrou]

I open it everytime I stop the cascade :)

[kayl]

maybe 4 foot with valve

Im gonna use 1/4 " on my commercial oil sep

[n00b 0f l337]

But what length without valve? I'll probably try 10" and watch the sight glass when I first boot up the 2nd stage.

[wdrzal]

If you guys don't want to buy them,why don't you guys have some mini compatitions to design DIY oil seperators.receivers,accumalotors and the like.

guys could post diy designs and they can be evaluated for safety,fuctionality and construction time and cost.

come up with a automatic oil seperator thats safe,cheap and easy to build for your first task.;)

[hatemi]

I use about 1m of 0.031. And as I said earlier the inpact on the sytem is not that big.

[n00b 0f l337]

come up with a automatic oil seperator thats safe,cheap and easy to build for your first task.
I doubt I can say I have the proper tools to take a cascade and tool around with the oil seperator for best performance while keeping it cheap and DIY. But I will say I'm willing to try the best design I see.
ANd I will be using my own design, I'll talk more bout it when I build my first cascade (upcoming weeks)

[quintus]

i got the y is there a valve on the oil return on my thong for ages
now i get it
Regards to all,
q

[n00b 0f l337]

I secured a packless valve on ebay for $20 shipped today, but I'd still like to see about getting no-valve working.

[jinu117]

I secured a packless valve on ebay for $20 shipped today, but I'd still like to see about getting no-valve working.
If you leave it open... it's like not having one :) So give it a go. I noticed with all these questions you are asking lately that you are building cascade it seems. Good luck to you :)

[n00b 0f l337]

If you leave it open... it's like not having one So give it a go. I noticed with all these questions you are asking lately that you are building cascade it seems. Good luck to you
I'm securing up my last doubts before starting the high stage Friday/Saturday.
Biggest problem now is metering devices.

[wdrzal]

noob have you ever buily a single, i don't recall seeing one but I don't follow every thread,

[n00b 0f l337]

2x chillers, 2x direct die, and an air chiller wdrzal.

[targ]

If you guys don't want to buy them,why don't you guys have some mini compatitions to design DIY oil seperators.receivers,accumalotors and the like.

guys could post diy designs and they can be evaluated for safety,fuctionality and construction time and cost.

come up with a automatic oil seperator thats safe,cheap and easy to build for your first task.;)


well i can provide the safety evaulation if this happens...
im a (nearly) qualified mechanic engineer, so i can find safe thickness and shapes etc

but im too busy at the moment to do any design myself :(

targ

[jinu117]

If you guys don't want to buy them,why don't you guys have some mini compatitions to design DIY oil seperators.receivers,accumalotors and the like.

guys could post diy designs and they can be evaluated for safety,fuctionality and construction time and cost.

come up with a automatic oil seperator thats safe,cheap and easy to build for your first task.;)

Oilsep with autofloat DIY probably will cost too much to bother is my guess :) Just need to find good source to get it without all the mark ups... Receiver, I find these selling rather cheap to bother unless I am looking for smaller capacity one more suitable for our use. Accumulator... ... regular spun type is easy enough to make and doesn't cost too much. However, the proper U bend type ones... if you look at pricing of copper tube that can give you good u bend tube in... isn't too cheap. Bit marginal on money saving factor really :P

[n00b 0f l337]

Accumulator... ... regular spun type is easy enough to make and doesn't cost too much. However, the proper U bend type ones... if you look at pricing of copper tube that can give you good u bend tube in... isn't too cheap. Bit marginal on money saving factor really :P
Ebay, search 2" accumulator there $2 a pop.

[jinu117]

Ebay, search 2" accumulator there $2 a pop.

Thats the copper one... u bend one looks totally differe :P I can just braze bigger tubing in for those. Still not a bad price at all.

[wdrzal]

you just need soft copper that comes in rolls to make a U bend.

The smaller the tube ,the tighter the possible radius. Here is a 3/8" tube bent in a u, The OD of the radius is 3 inches. Thats the smallest radius I can bend for that size tube.

[jinu117]

you just need soft copper that comes in rolls to make a U bend.

The smaller the tube ,the tighter the possible radius. Here is a 3/8" tube bent in a u, The OD of the radius is 3 inches. Thats the smallest radius I can bend for that size tube.

Uhmmm yummy tools!
yup so we need at least 3" id pipe for home made... meaning... cost... :P 3" copper isn't cheap...

[wdrzal]

you can buy those mandrel bent U's that are smaller,like on the side of condensors.Then braze on your up tubes.