I think you need 4 compressors to make cascade more stable :D :D :D
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I think you need 4 compressors to make cascade more stable :D :D :D
holy shiat nice lathe :P
thanks lads just got the unit back from powder coat
masell i could not afford to run any more comps:D
http://www.benchtec.co.uk/images/baz...p/CIMG0960.jpg
http://www.benchtec.co.uk/images/baz...p/CIMG0961.jpg
http://www.benchtec.co.uk/images/baz...p/CIMG0963.jpg
http://www.benchtec.co.uk/images/baz...p/CIMG0964.jpg
Well damn.
Keep building it. :D
Looking very good baz, sorry I just had to have the same colour as you had chosen; it just looks so good up against them black compressors I had to have it.
hehe paul
its starting to come together
just been offering up the parts
http://www.benchtec.co.uk/images/baz...m/DSC01300.jpg
http://www.benchtec.co.uk/images/baz...m/DSC01302.jpg
http://www.benchtec.co.uk/images/baz...m/DSC01303.jpg
Nice frame :up:
The lower section will be boxed in with stainless steel panels the underside will be aluminium sheet with and extractor fan assembly to the rear of the unit opposite the condenser
I will also be fitting a smaller de-super heater (air) to the first stage as well as a water de-super heater which i will use depending on the location and ambiant
The upper section has to take the 2x expansion tanks, 2x plated hx boxed, 2x de-super heaters, gauges and electrics all mounted on an aluminium base
There will be a removable top box which will also have stainless steel panels this will be around
14 inches higher then you can see now
The unit as it is now is around 3 feet 6 inches tall
Looking good, looking very good. Only one thing, where'd you get that second temprite 900 used like that? Hehe must be a good source ;)
hehe that came out of cascade 4 nolQuote:
Originally Posted by n00b 0f l337
cascade 4 is now back to cascade 3 and will be going to one of our bench team
and i had to leave the other 900 in that unit so i only had to buy the one for this unit
O gotcha!
Good source indeed ;)
Hahaha I love the 900's though, hard to beat size to performance ratio.
i would only use thetemprite 900 i love them
How much that powder coating cost you? And how did you weld the stand up? I really wish I had a way to weld...
its called a welder nol :D Looks to me like he miged it. Looking good Bazx.Quote:
Originally Posted by n00b 0f l337
yes its mig welded its ot to tricky to get the hang of it
the powder coat came to £90 which is around 2x your money
Yeah, well wow, worth it it would seem.
Quote:
Originally Posted by bazx
Nah. You just gotta keep the temperature down low. Just tack it together in spots and then finish it later. Towards the edges it tends to get hotter because less material for the heat. A little trick is once everything is tacked together you can lay one hand flat and then the hand with the welder ontop of that and use it as a pivot. It will keep your hand steady and allow for a nice bed.
I wish I had your hands bazx... :rolleyes: :)
Quote:
Originally Posted by Clemmaster
lol and i would have your brains:)
clem do you think r23 in the second stage using a tev would give me enough to condense the r14
i have never used r23 tev before but they are available and might give me -82
or would it need to be closer to -90 which would need r1150
thanks baz
Should be possible with R23. I even would recommend this solution. Look at the cascade of august123.
Rotary can run with high discharge pressure so I'd say no reason? :shrug:Quote:
Originally Posted by bazx
I don't know if you would get the capacity you want in the end, I didn't search data on your compressors so I can't tell you right now. Maybe others who already played with it can repport their experience.
I've made a comparison of 2nd stage refrigerant in the -8x range, you've got cooling capacity with a SC21CLX, and condensing rejection assuming a desuperheated vapour entering the HX with 20°C (or 25°C I don't remember). On the right you've got the increase in rejection compared to capacity.
If it can help you with your choice : http://clemmaster.free.fr/2nd_stage_refrigerant.jpg
:)
Edit: and using R1150 in the -90° range would require a "low" displacement, see the capacity and condensing rejection you get with a poor 21cc (poor volumetric efficiency), that's almost 1.2kw needed @ -35°C on first stage (assuming 5K CTD in the HX), that requires a ~30cc in first stage :p:
Edit2: That's a modelization of the SC21CLX of course :D
Hi baz,
I made some more calculations base on a 30.7cc/rev rotary (see the compressor settings, they're for piston compressor but they aren't far from rotaries I think, I checked with a system Tom made). Obviously the values aren't 100%, the modelisation isn't finished yet but they give accurate enough values to start thinking with it. :)
http://clemmaster.free.fr/bazx.jpg
Look at the operating conditions at the bottom before the rest :p:. I tried with several operating conditions/refrigerants and you can see that it may work properly with R23 in the -13x°C range as well.
- I think with the R23 you can use the operating conditions as follows (keep in mind that 1st stage is a 30.7cc here, you'll get an increase in cooling capacity with the 36.7cc/rev one) : ~2/4/8
R1150 @ -90°C on second stage is overkill, you won't be able to condense it at -35°C (@-95°C neither) without having a severe flood back.
But there's something you can do in the -95 ~ -100 range : not use a desupperheater in third stage, that would provide enough load to prevent from liquid return in second stage. You can add a desuperheater (condenser like as usual), turn of the fan and block any passive airflow then you can turn it on if needed :shrug: --> The staging would be : ~2/7/9
I don't know what temperature and load you're aiming so we can't give any conclusion for the moment, except that R23 will work properly :up:
thanks very much for all the work here clem
i will be going with the r23 tev and will do as you suggest for the de-super on the third stage
thanks baz:)