Here's a link to a video of water in an Vacuum chamber boiling then freezing
http://www.youtube.com/watch?v=Par-jcV2tPc
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Here's a link to a video of water in an Vacuum chamber boiling then freezing
http://www.youtube.com/watch?v=Par-jcV2tPc
is this what happens when you pull a vacume to quickly ? as i remember being told something like this but i seem to have a gap in my memory as to who and when
Yeah, thats it mateQuote:
Originally Posted by simon@parker
Its the reason behind a triple vac
When you pull a vacuum it will vapourise water untill it has used up the available heat/energy & then the water just freezes
Mmmm, nice video Chillerman, where did you filmed this or get it?
Had it so long now mate - can't remember where it came from :eek:Quote:
Originally Posted by Peter_1
Well, in fact, I made this video ;-) And it is not in an environmental chamber but in a vacuum chamber. There are some pictures of this chamber on RE
OOH ! I hope your not gonna have me for copyright, Boss :eek:Quote:
Originally Posted by Peter_1
Good job I did not try to tell you porkies (lies) :D
Hi
every apprentice should veiw this video.
Amazing. Thanks to the OP & Peter... If you have more such useful videos, I'd love to see them.
I'm a 2nd year apprentice and i think that was a brilliant video...but if water freezes during the vac will that not just leave ice/water/moisture in the pipe?
You are right and not right. This bottle was placed in vacuum chamber where the vacuum process is going very, very fast with huge pumps. Imagine the pumps stored in a place as big as a small house for a chamber of +/- 2 x2 m (space filled with pumps stacked and with the chamber is +/- 10 x 15 m) Then the achived vacuum is something we only can dream of..they'"re working on a molecular level of vacuum, UHV (ultra High Vacuum). UHV is in the range of 10 (-79) Pa or 140 (-9) torr. Some systems uses additional molecular vacuum pumps to speed up the process. Price: < 25,000 €/pump and there are sometimes 8 pumps on a chamber.http://t0.gstatic.com/images?q=tbn:A...0-r-BrxBm5apunQuote:
Originally Posted by newbie
The vacuum process is going that fast that the needed energy to vaporize isn't going fast enough through the plastic of the bottle with freezing as a result. The energy is faster removed then it is added.
What we better had done was continuing the process and we should have seen sublimation of the ice. But the operator of this machine can't afford long standstills of his machine.
We almost bought one 2 years ago at Philips Brussels where we should have use it to freezedry documents after water damages of inventories. This is a very nice application of this chambers.
RB - do we get an explanation then
No can do as I wasn't there...Quote:
Originally Posted by chillerman2006
Well not 100% & running the risk here of becoming Peter's signature
We have 3 gaseous base elements here 2 in the water and 1 with the introduction of nitrogen
along with any refrigerant that may or may not be present
Whilst pulling a vacuum oil is also often removed
The frozen substance is a mixture of H20+N (or maybe refrigerant) + oil
caused by pulling a vacuum too quickly & the hygroscopic feature of the oil in use
I have been informed that using the larger vac pumps on smaller systems is an issue
No experience of this though as I do not normally work on them
do not have mr o'brien 's email to hand or that copy of service engineer
can anyone confirm ?
@Peter_1....so eventually the vacuum would evaporate the ice?
http://hvac-talk.com/vbb/showthread.php?t=378742Quote:
Originally Posted by chillerman2006
cheers, I'll have a butchers after dinnerQuote:
Originally Posted by r.bartlett
hey
can not log in to that site + do not wish to join
i am expecting the old argument of nitrogen does not help evac - just pushes out oxy
the answer we need though is exactly what is the substance in the video
better to tell us than post a link no-one can view surely
:rolleyes:
As I say I wasn't there as this was well after I left fridgetech so I haven't got a clue..Quote:
Originally Posted by chillerman2006
Get out of it - if you worked with Marc you must do, surelyQuote:
Originally Posted by r.bartlett
You make me jealous of any training you got there now!
If we look at his fingers, it seems that the only residue is oil. I would suspect that there is refrigerant trapped into a water/oil mix (solid), when heat is added the refrigerant just boils out of the mix (similar to the reason you have a crankcase heater)
Thanks Mad
much appreciated
:D
It also makes a pingy noise as it goes round the bends in the pipework....
Interesting - I have a cone I use for listening to bearings & now pipework, yeah makes senseQuote:
Originally Posted by monkey spanners
Classic!! Honesty is always the best policy;). I've always liked the saying, what goes around, comes around.Quote:
Originally Posted by chillerman2006
Yep, I like to be up front & honest with peopleQuote:
Originally Posted by mikeref
& when I read back through the posts, I think Peter tactfully give me just enough rope to hang myself :D