|
Hello...
I need to make vacuum in range 5 to 10 mBar. What device to use for that. I need to evacuate aprox 5 litre box but I do not have electricity on place where I need to do that. What options I have?
Thanks
|
On 6/6/2011 5:55 AM, slavkok wrote: Hello...
I need to make vacuum in range 5 to 10 mBar. What device to use for that. I need to evacuate aprox 5 litre box but I do not have electricity on place where I need to do that. What options I have?
Thanks Prepare bottles of vacuum. transfer them to container, on site? :-) Brian W
|
Fill the box with steam, and then freeze it? Theory says that should get you to 6 millibars (0.6 kilopascals).
Brian -- If he has a 5 liter box at a 1,013.25 millibars, and he wants to
get to 10 millibars, wouldn't he need to attach a completely empty 511.625 liter vacuum chamber to it in order to get both the box and the vacuum chamber to equalize at 10 millibars?
Finding and evacuating a 136 gallon vacuum chamber (or larger if he can only evacuate it to a few millibars) might not be all that cheap.
If freezing it is difficult where there is no electricity, perhaps filling the box
with molten lead, and then emptying it through a 3 foot pipe in the bottom might work. The weight of the molten lead would leave a vacuum as it poured out into a holding basin, much like the original mercury barometers. Lead/tin
solder could also be used, to get a lower melting point, but he would need a longer pipe, since the density is 8.79 instead of leads 11.34.
5 liters of solder weighs a little under 100 pounds. At $6 per pound for 80/20
lead/tin solder, that's $600.00.
He could get a cheap vacuum pump like the ones they use to reclaim Freon from car air conditioners for about $100, and an inverter for a car for about
$20 (to convert the car's 12 volts DC into 120 volts AC). It might take all day for the pump to do the job, but it's cheaper than lead. ;-)
----- Get a free science project every week! ""
On Mon, Jun 6, 2011 at 3:14 PM, brian whatcott <betwys1@...> wrote:
?
On 6/6/2011 5:55 AM, slavkok wrote:
> Hello...
>
> I need to make vacuum in range 5 to 10 mBar. What device to use for that. I need to evacuate aprox 5 litre box but I do not have electricity on place where I need to do that. What options I have?
>
> Thanks
Prepare bottles of vacuum. transfer them to container, on site? :-)
Brian W
|
Inexpensive gasoline-powered electrical
generator.
?
-Christopher Erickson
Consulting
Engineer
Summit Kinetics
Waikoloa, HI 96738
?
toggle quoted message
Show quoted text
Fill
the box with steam, and then freeze it?
Theory says that should get you to 6 millibars (0.6 kilopascals).
Brian -- If he has a 5 liter box at a 1,013.25 millibars, and he wants
to
get to 10 millibars, wouldn't he need to attach a completely empty
511.625
liter vacuum chamber to it in order to get both the box and the
vacuum
chamber to equalize at 10 millibars?
Finding and evacuating a 136 gallon vacuum chamber (or larger if he can
only
evacuate it to a few millibars) might not be all that cheap.
If freezing it is difficult where there is no electricity, perhaps
filling the box
with molten lead, and then emptying it through a 3 foot pipe in the
bottom
might work. The weight of the molten lead would leave a vacuum as it
poured
out into a holding basin, much like the original mercury barometers.
Lead/tin
solder could also be used, to get a lower melting point, but he would
need
a longer pipe, since the density is 8.79 instead of leads 11.34.
5 liters of solder weighs a little under 100 pounds. At $6 per pound for
80/20
lead/tin solder, that's $600.00.
He could get a cheap vacuum pump like the ones they use to reclaim
Freon
from car air conditioners for about $100, and an inverter for a car for
about
$20 (to convert the car's 12 volts DC into 120 volts AC). It might take
all day
for the pump to do the job, but it's cheaper than lead.
;-)
----- Get a free science project every week! ""
On Mon, Jun 6, 2011 at 3:14 PM, brian whatcott <betwys1@...>
wrote:
?
On 6/6/2011 5:55 AM, slavkok wrote:
>
Hello...
>
> I need to make vacuum in range 5 to 10 mBar. What
device to use for that. I need to evacuate aprox 5 litre box but I do not
have electricity on place where I need to do that. What options I
have?
>
> Thanks
Prepare bottles of vacuum. transfer
them to container, on site? :-) Brian W
|
On 6/6/2011 5:44 PM, Simon Quellen Field wrote:
Fill the box with steam, and then freeze it?
Theory says that should get you to 6 millibars (0.6
kilopascals).
Brian -- If he has a 5 liter box at a 1,013.25 millibars, and
he wants to
get to 10 millibars, wouldn't he need to attach a completely
empty 511.625
liter vacuum chamber to it in order to get both the box and
the vacuum
chamber to equalize at 10 millibars?
Though the suggestion was offered in jest, I suppose I need to
answer "No" to your
estimate: connecting one big vacuum container, is rather different
from connecting
numerous smaller bottles in turn.
Isn't it?
Brian W
|
On 6/6/2011 6:04 PM, Christopher Erickson wrote:
Inexpensive gasoline-powered
electrical generator.
?
-Christopher
Erickson
Consulting Engineer
Summit Kinetics
Waikoloa, HI 96738
Talking about gas powered generators - a usable roughing pump
is provided by a vacuum tube connected to the inlet manifold
of an idling 4 stroke. Then there's the venturi pump you
connect to the spare tire...
:-)
Brian W
|
How much suction could you get from a 4cyl engine if you took one
cylinder out of service and used it as your vacuum pump? Not easy or
cheap, but probably do-able.
But really I'd second the refrigeration vac-pump plus inverter idea,
will get you there and you probably used your car to get to the
location anyway.....
Cheers, Thomas J.
On 7/06/2011 9:10 AM, brian whatcott wrote:
toggle quoted message
Show quoted text
?
On 6/6/2011 6:04 PM, Christopher Erickson wrote:
Inexpensive
gasoline-powered electrical generator.
?
-Christopher Erickson
Consulting Engineer
Summit Kinetics
Waikoloa, HI 96738
Talking about gas powered generators - a usable
roughing pump is provided by a vacuum tube connected
to the inlet manifold of an idling 4 stroke. Then
there's the venturi pump you connect to the spare
tire...
:-)
Brian W
|
S, slavkok pi?e:
Hello...
I need to make vacuum in range 5 to 10 mBar. What device to use for that. I need to evacuate aprox 5 litre box but I do not have electricity on place where I need to do that. What options I have?
Thanks
Hello...
I got few orthodox sugestions. But all seems to be inposible to do.
... to get vaccum in container the container is to big.
... to buy gassoline powered generator is out of question
... to use heavy metal to evacuate is to danger and near inpossible
to do.
... to use steam seem's possible but not in my case. (it wil
saturate content)
to explain why I need that.
In remote location (lodge) I wan't refrigerator to keep foot in cold
enought place. Gas refrigerator is just too expensive here and I
like to experiment. So I plan to make adsorption refrigerator. It's
simple and can be cheap. Just need isolated box with some evaporator
inside and canister filled with zeolite. All thing should be sealed
and put under vacuum. When watter starts to boil the temperature
will drop. So I need to 'pump' it until the water is colled down to
aprox 7 degres celsius (10 mbar) and that's all. The zeolite then
suck that water vapour until saturate. With good insulation it
should work for at least 2 days or at least 7 days if dorr is keept
close. So I need to regenerate it at least once per week or more if
the dor was frequently oppened. I search for some hand driven pump
but not happy with what I fund till now.
Here is links what can be done...
and patent here
|
--- In VacuumX@..., "slavkok" <eslavko@...> wrote:
Hello...
I need to make vacuum in range 5 to 10 mBar. What device to use for that. I need to evacuate aprox 5 litre box but I do not have electricity on place where I need to do that. What options I have?
Thanks
Hello... I got few orthodox sugestions. But all seems to be inposible to do. ... to get vaccum in container the container is to big. ... to buy gassoline powered generator is out of question ... to use heavy metal to evacuate is to danger and near inpossible to do. ... to use steam seem's possible but not in my case. (it wil saturate content) to explain why I need that. In remote location (lodge) I wan't refrigerator to keep foot in cold enought place. Gas refrigerator is just too expensive here and I like to experiment. So I plan to make adsorption refrigerator. It's simple and can be cheap. Just need isolated box with some evaporator inside and canister filled with zeolite. All thing should be sealed and put under vacuum. When watter starts to boil the temperature will drop. So I need to 'pump' it until the water is colled down to aprox 7 degres celsius (10 mbar) and that's all. The zeolite then suck that water vapour until saturate. With good insulation it should work for at least 2 days or at least 7 days if dorr is keept close. So I need to regenerate it at least once per week or more if the dor was frequently oppened. I search for some hand driven pump but not happy with what I fund till now. Here is links what can be done... and patent here Slavko
|
I think you can make falling water get you that kind of vacuum.
You would need a thicker pipe where you spray water downwards, then a funnel shape at the bottom of that and connect it to a hose. A bit like a oil diffusion pump, just vertical.
The hose need to have at least 11m drop so it can pull some air with it on its way down. It also got to be just the right thickness to trap the air and also allow for a decent flow.
The drop could be a hill, it's the vertical distance that counts.
I can think of all kinds of problems with this design, but it's simple enough that you can power it all by hand. Making it more reliable will need a lot of tinkering. Also, it needs icy cold water (:
toggle quoted message
Show quoted text
--- In VacuumX@..., "slavkok" <eslavko@...> wrote:
Hello...
I need to make vacuum in range 5 to 10 mBar. What device to use for that. I need to evacuate aprox 5 litre box but I do not have electricity on place where I need to do that. What options I have?
Thanks
|
S, knegge pie: I think you can make falling water get you that kind of vacuum.
You would need a thicker pipe where you spray water downwards, then a funnel shape at the bottom of that and connect it to a hose. A bit like a oil diffusion pump, just vertical.
The hose need to have at least 11m drop so it can pull some air with it on its way down. It also got to be just the right thickness to trap the air and also allow for a decent flow.
The drop could be a hill, it's the vertical distance that counts.
I can think of all kinds of problems with this design, but it's simple enough that you can power it all by hand. Making it more reliable will need a lot of tinkering. Also, it needs icy cold water (:
This seems like ejector for me. And presure reached can't be under water vapour presure. So as you write the vater should be ici. I was tryed (far ago) the ejector pump in water tap pipe and as I remember I got 50 mBar presure with 5 Bar water at aprox 15 Centigrade. Not bad but stil to high. I tryed design from ie just PVC pipe attached to gauge and rollers and can get under 1 mBar. Just not sure how long I need to 'roll' to evacuate 5 liter box. Maybe some kind of peristaltic pump? And how to measure vacuum? Some idea? (Ocassionaly I can borrow digital instrument but just for few hours or a day max) I thinking on to build pirani gauge, but afraid that this type of instrument is for lower presures. The another idea is to just make small chamber with little watter and thermometer. As watter evaporate (under vacum) it will coll down. And with reading temperature we can calculate the pressure?!? Does somebody try that already? Slavko
|
Sometimes it helps to look at the actual problem you want to solve, rather than to help solve it in the least efficient way.
""
""
""
But since this is a group interested in vacuum, I'll also offer what you asked for.
""
""
""
""
Your car already has a generator. ""
""
-----
Get a free science project every week! ""
On Tue, Jun 7, 2011 at 1:58 AM, Slavko Kocjancic <eslavko@...> wrote:
S, knegge pi?e:
> I think you can make falling water get you that kind of vacuum.
> You would need a thicker pipe where you spray water downwards, then a funnel shape at the bottom of that and connect it to a hose. A bit like a oil diffusion pump, just vertical.
> The hose need to have at least 11m drop so it can pull some air with it on its way down. It also got to be just the right thickness to trap the air and also allow for a decent flow.
> The drop could be a hill, it's the vertical distance that counts.
>
> I can think of all kinds of problems with this design, but it's simple enough that you can power it all by hand. Making it more reliable will need a lot of tinkering. Also, it needs icy cold water (:
>
This seems like ejector for me. And presure reached can't be under water
vapour presure. So as you write the vater should be ici. I was tryed
(far ago) the ejector pump in water tap pipe and as I remember I got 50
mBar presure with 5 Bar water at aprox 15 Centigrade. Not bad but stil
to high.
I tryed design from
ie just PVC pipe attached to gauge and rollers and can get under 1 mBar.
Just not sure how long I need to 'roll' to evacuate 5 liter box. Maybe
some kind of peristaltic pump?
And how to measure vacuum? Some idea? (Ocassionaly I can borrow digital
instrument but just for few hours or a day max) I thinking on to build
pirani gauge, but afraid that this type of instrument is for lower
presures. The another idea is to just make small chamber with little
watter and thermometer. As watter evaporate (under vacum) it will coll
down. And with reading temperature we can calculate the pressure?!? Does
somebody try that already?
Slavko
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|
On Tue, Jun 7, 2011 at 2:14 AM, Slavko Kocjancic <eslavko@...> wrote:
S, slavkok pi?e:
Hello...
I need to make vacuum in range 5 to 10 mBar. What device to use for that. I need to evacuate aprox 5 litre box but I do not have electricity on place where I need to do that. What options I have?
Thanks
Hello...
I got few orthodox sugestions. But all seems to be inposible to do.
... to get vaccum in container the container is to big.
... to buy gassoline powered generator is out of question
... to use heavy metal to evacuate is to danger and near inpossible
to do.
... to use steam seem's possible but not in my case. (it wil
saturate content)
to explain why I need that.
In remote location (lodge) I wan't refrigerator to keep foot in cold
enought place. Gas refrigerator is just too expensive here and I
like to experiment. So I plan to make adsorption refrigerator. It's
simple and can be cheap. Just need isolated box with some evaporator
inside and canister filled with zeolite. All thing should be sealed
and put under vacuum. When watter starts to boil the temperature
will drop. So I need to 'pump' it until the water is colled down to
aprox 7 degres celsius (10 mbar) and that's all. The zeolite then
suck that water vapour until saturate. With good insulation it
should work for at least 2 days or at least 7 days if dorr is keept
close. So I need to regenerate it at least once per week or more if
the dor was frequently oppened. I search for some hand driven pump
but not happy with what I fund till now.
Here is links what can be done...
and patent here
You might want to bring a propane cylinder along and use something like the 'Icyball' to do your cooling.
Googel 'Icyball' for information on how to build this refrigeration device.
Darald
|
S, Simon Quellen Field pie:
Sometimes it helps to look at the actual problem you want to
solve,
rather than to help solve it in the least efficient way.
""
""
""
But since this is a group interested in vacuum, I'll also
offer what you asked for.
""
""
""
""
Your car already has a generator.
""
""
A lot of links...
Now the answers...
The refrigerators based on Peltie element (these under $100) are so
ineficient and thus unusable. I have two of them but they pull 40W
from my solar system and was claimed that they can get 20 centigrade
under surounding temperature. That's just not true. If I fill that
ones with already cooled stuff they slowly warm up to aprox 15
centigrade environment temperature. And this just isn't enought. The
expensive one (over $250) intended for boat or something does do the
job. But need a lot of power (at least when starting) so again not
suitable. Gas powered refrigerator's (good for me) are just
overpriced here.
On the gauges in link I think it's not possible to see if pressure
is 30 or 15 or 5 mbar. And accuracy suffer.
The pump on link seems nice one... ...if that price is the final
price. But isn't. And as I wan't to pump air and watter vapour the
oil can be contaminated to quick. But it's nice pump...
And at least I have inverter already mounted for some power tools
but all other thing is for 12 or 24V.
ahh.. the hand pump... Can that one reach 10mbar?!? I don't think
that 100mBar is reachable.
Sorry... but thanks for all suggestions.
|
S, o1bigtenor pi?e:
On Tue, Jun 7, 2011 at 2:14 AM, Slavko
Kocjancic <eslavko@...>
wrote:
S, slavkok pi?e:
Hello...
I need to make vacuum in range 5 to 10 mBar. What device to use for that. I need to evacuate aprox 5 litre box but I do not have electricity on place where I need to do that. What options I have?
Thanks
Hello...
I got few orthodox sugestions. But all seems to be inposible
to do.
... to get vaccum in container the container is to big.
... to buy gassoline powered generator is out of question
... to use heavy metal to evacuate is to danger and near
inpossible to do.
... to use steam seem's possible but not in my case. (it wil
saturate content)
to explain why I need that.
In remote location (lodge) I wan't refrigerator to keep foot
in cold enought place. Gas refrigerator is just too
expensive here and I like to experiment. So I plan to make
adsorption refrigerator. It's simple and can be cheap. Just
need isolated box with some evaporator inside and canister
filled with zeolite. All thing should be sealed and put
under vacuum. When watter starts to boil the temperature
will drop. So I need to 'pump' it until the water is colled
down to aprox 7 degres celsius (10 mbar) and that's all. The
zeolite then suck that water vapour until saturate. With
good insulation it should work for at least 2 days or at
least 7 days if dorr is keept close. So I need to regenerate
it at least once per week or more if the dor was frequently
oppened. I search for some hand driven pump but not happy
with what I fund till now.
Here is links what can be done...
and patent here
You might want to bring a propane cylinder along and use
something like the 'Icyball' to do your cooling.
Googel 'Icyball' for information on how to build this
refrigeration device.
Darald
The IcyBall is near same functionality as zeolite/watter. Just other
(poision) components and presure instead vacuum.
I do research what is suitable for me and found:
IcyBall??? -??? to danger
DryIce??? -??? not available here
Regular ice block.?? - Used now. Good for up to 2 day.
Adsorption Activated carbon/alcohol or zeolite water - Probably best
way. As already have zeolite want to try. drawback need to evacuate
system every time, or to make closed one with condenser and other
stuf..
Slavko
|
On Tue, Jun 7, 2011 at 10:40 AM, Slavko Kocjancic <eslavko@...> wrote:
S, o1bigtenor pi?e:
The IcyBall is near same functionality as zeolite/watter. Just other
(poision) components and presure instead vacuum.
I do research what is suitable for me and found:
IcyBall??? -??? to danger
DryIce??? -??? not available here
Regular ice block.?? - Used now. Good for up to 2 day.
Adsorption Activated carbon/alcohol or zeolite water - Probably best
way. As already have zeolite want to try. drawback need to evacuate
system every time, or to make closed one with condenser and other
stuf..
Slavko
Is suggested the Icyball because if YOU can silver solder you can make a system which is very cheap to run. As I am a professional welder its not too hard for me. It is a possible solution!
Darald
|
On 6/7/2011 10:10 AM, Slavko Kocjancic wrote:
S, Simon Quellen Field pie:
Sometimes it helps to look at the actual problem you want
to solve,
rather than to help solve it in the least efficient way.
""
""
""
But since this is a group interested in vacuum, I'll also
offer what you asked for.
""
""
""
""
Your car already has a generator.
""
""
A lot of links...
Now the answers...
The refrigerators based on Peltie element (these under $100) are
so ineficient and thus unusable. I have two of them but they pull
40W from my solar system and was claimed that they can get 20
centigrade under surounding temperature. That's just not true. If
I fill that ones with already cooled stuff they slowly warm up to
aprox 15 centigrade environment temperature. And this just isn't
enought. The expensive one (over $250) intended for boat or
something does do the job. But need a lot of power (at least when
starting) so again not suitable. Gas powered refrigerator's (good
for me) are just overpriced here.
On the gauges in link I think it's not possible to see if pressure
is 30 or 15 or 5 mbar. And accuracy suffer.
The pump on link seems nice one... ...if that price is the final
price. But isn't. And as I wan't to pump air and watter vapour the
oil can be contaminated to quick. But it's nice pump...
And at least I have inverter already mounted for some power tools
but all other thing is for 12 or 24V.
ahh.. the hand pump... Can that one reach 10mbar?!? I don't think
that 100mBar is reachable.
Sorry... but thanks for all suggestions.
Lessee: you didn't want to connect a series of vacuum bottles -
instead you want to connect a series of narrow bore vaccum tubes (in
effect) and this is somehow better? :-)
Brian W
|
A modern, high-efficiency?RV refrigerator, a propane bottle or
two, a 12V
marine battery, a 50W solar panel and an MPPT
solar charge controller.
?
No reason to reinvent the wheel.
?
Adding a bunch more conditions and rules is just
silly.
?
-Christopher Erickson
Consulting
Engineer
Summit Kinetics
Waikoloa, HI 96738
toggle quoted message
Show quoted text
On
6/7/2011 10:10 AM, Slavko Kocjancic wrote:
S, Simon Quellen Field pi?e:
Sometimes it helps to look at the actual problem you want to
solve,
rather than to help solve it in the least efficient way.
""
""
""
But since this is a group interested in vacuum, I'll also offer what
you asked for.
""
""
""
""
Your car already has a generator.
""
""
A lot of links...
Now the
answers...
The refrigerators based on Peltie element (these under $100)
are so ineficient and thus unusable. I have two of them but they pull 40W
from my solar system and was claimed that they can get 20 centigrade under
surounding temperature. That's just not true. If I fill that ones with
already cooled stuff they slowly warm up to aprox 15 centigrade environment
temperature. And this just isn't enought. The expensive one (over $250)
intended for boat or something does do the job. But need a lot of power (at
least when starting) so again not suitable. Gas powered refrigerator's (good
for me) are just overpriced here.
On the gauges in link I think it's not
possible to see if pressure is 30 or 15 or 5 mbar. And accuracy
suffer.
The pump on link seems nice one... ...if that price is the
final price. But isn't. And as I wan't to pump air and watter vapour the oil
can be contaminated to quick. But it's nice pump...
And at least I have
inverter already mounted for some power tools but all other thing is for 12
or 24V.
ahh.. the hand pump... Can that one reach 10mbar?!?? I
don't think that 100mBar is reachable.
Sorry...? but thanks for
all
suggestions.
|
An inverter, a car, a few extra gallons of fuel, and a cheap small refrigerator. ""
"" ""
During power outages here up on the mountain, I used to idle my truck while it powered an inverter. That powered the house all day, including a large standard refrigerator. For a little refrigerator like one of the above,
you won't need a 1,000 watt inverter -- more like 200 to 300 watts at most. And at night, you don't need to power the fridge at all, since the door will be closed all night.
----- Get a free science project every week! ""
?
A modern, high-efficiency?RV refrigerator, a propane bottle or
two, a 12V
marine battery, a 50W solar panel and an MPPT
solar charge controller.
?
No reason to reinvent the wheel.
?
Adding a bunch more conditions and rules is just
silly.
?
-Christopher Erickson
Consulting
Engineer
Summit Kinetics
Waikoloa, HI 96738
On
6/7/2011 10:10 AM, Slavko Kocjancic wrote:
S, Simon Quellen Field pi?e:
Sometimes it helps to look at the actual problem you want to
solve,
rather than to help solve it in the least efficient way.
""
""
""
But since this is a group interested in vacuum, I'll also offer what
you asked for.
""
""
""
""
Your car already has a generator.
""
""
A lot of links...
Now the
answers...
The refrigerators based on Peltie element (these under $100)
are so ineficient and thus unusable. I have two of them but they pull 40W
from my solar system and was claimed that they can get 20 centigrade under
surounding temperature. That's just not true. If I fill that ones with
already cooled stuff they slowly warm up to aprox 15 centigrade environment
temperature. And this just isn't enought. The expensive one (over $250)
intended for boat or something does do the job. But need a lot of power (at
least when starting) so again not suitable. Gas powered refrigerator's (good
for me) are just overpriced here.
On the gauges in link I think it's not
possible to see if pressure is 30 or 15 or 5 mbar. And accuracy
suffer.
The pump on link seems nice one... ...if that price is the
final price. But isn't. And as I wan't to pump air and watter vapour the oil
can be contaminated to quick. But it's nice pump...
And at least I have
inverter already mounted for some power tools but all other thing is for 12
or 24V.
ahh.. the hand pump... Can that one reach 10mbar?!?? I
don't think that 100mBar is reachable.
Sorry...? but thanks for
all
suggestions.
|
S, o1bigtenor pi?e:
Is suggested the Icyball because if YOU can silver solder
you can make a system which is very cheap to run. As I am a
professional welder its not too hard for me. It is a possible
solution!
I don't have equipment for silver soldering, just for soft
soldering. IcyBall seems atractive but the presence of ammonia take
me off. Long ago I checked that topic and found a lot of problems
with that and accidents. So I avoid that. But thanks for
sugesstions.
Slavko.
|
Simon Quellen Field
Christopher Erickson
Daniel Ekman SA2KNG