Scary Water Pump

[N. Thornton]

Hi


I thought I'd ask about this. Is it possible to use a conventional
cylinder vacuum cleaner (old sausage dog type) to pump clean water?
These cleaners work by passing the filterd air stream through the
motor to cool it, so the water would go thru motor as well.

For any unaware person reading this, don't do it as its clearly
dangerous, my question is whether its _possible_?


Regards, NT

 

[Baxter Basics]

yes- best to try it out in the bath first. Throw in a few handfulls of salt
before you get in to improve the efficiency.

 

[Ian Stirling]

Hi


I thought I'd ask about this. Is it possible to use a conventional
cylinder vacuum cleaner (old sausage dog type) to pump clean water?
These cleaners work by passing the filterd air stream through the
motor to cool it, so the water would go thru motor as well.

For any unaware person reading this, don't do it as its clearly
dangerous, my question is whether its _possible_?

I'd have to say no.
At least certainly no unaltered.
The rotor spins at some tens of thousands of RPM.
Even if it could keep this speed when water got to it, it'd be destroyed
by cavitation and general stress, as it's so lightly built.

Run at a few percent power, I think you would get some pumping action.
If pumping very clean/distilled water, the corrosion may not be that bad,
and you may get a reasonable life (few days of pumping continuously) as
contaminants will get washed away from the brushes rather than conducting
ionically.
Losses from "windage" due to the close gaps in the motor will be large.

 

[anthony wooldridge]

Hi


I thought I'd ask about this. Is it possible to use a conventional
cylinder vacuum cleaner (old sausage dog type) to pump clean water?
These cleaners work by passing the filterd air stream through the
motor to cool it, so the water would go thru motor as well.

For any unaware person reading this, don't do it as its clearly
dangerous, my question is whether its _possible_?

Definite no-no !
Water and air have vastly different viscocity.
Quite apart from the scary water/electricity aspects.
What about a Vax type wet/dry vacuum where
the water doesn't come in contact with the motor?
When the water container gets full you could automatically
empty it with a pressure switch/ electrical solenoid.
There is also a simpler way to do auto emptying using the
weight of water to trip a counterweighted flap.
Regards
Anthony

 

[Tony Williams]

I thought I'd ask about this. Is it possible to use a
conventional cylinder vacuum cleaner (old sausage dog type) to
pump clean water? These cleaners work by passing the filterd air
stream through the motor to cool it, so the water would go thru
motor as well.

I don't know how effective it might be, but you might
consider using the exhaust airflow to suck up the water.


------------------------------------
-->Airflow--> --> Air+Water -->
-----------------/ /----------------
/ /
/ /
Water

I'll think I'll patent that, call it a carburettor maybe.

 

[Graham]

I'd have to say no.
At least certainly no unaltered.
The rotor spins at some tens of thousands of RPM.
Even if it could keep this speed when water got to it, it'd be destroyed
by cavitation and general stress, as it's so lightly built.

(snip)

I have used one to pump air out of a barrel. Another pipe from the barrel
can be used to suck up water. You have to make sure that water level never
reaches the air pipe, and you can only run it briefly as there isn't enough
air going through the motor to cool it.

Graham

 

[Ian Stirling]

(snip)

I have used one to pump air out of a barrel. Another pipe from the barrel
can be used to suck up water. You have to make sure that water level never
reaches the air pipe, and you can only run it briefly as there isn't enough
air going through the motor to cool it.

If you can live with slightly lower vacuum, then you put a hole in the tube
from the barrel and allow cooling air in.

 

[Duncan Lees]

I don't know how effective it might be, but you might
consider using the exhaust airflow to suck up the water.


------------------------------------
-->Airflow--> --> Air+Water -->
-----------------/ /----------------
/ /
/ /
Water

I'll think I'll patent that, call it a carburettor maybe.

How about: /\ Vacuum
|
| |
| |
| |
------------------------------------| |
-->Airflow--> --> Air+Water |
-----------------/ /----------------| |
/ / _| |_
/ / | | |
/ / | \/ | Water
/ / |~~~~~|
/ / |_____|
Water

Would that work, or would all the water still end up in the vac?

-Duncan

 

[Tony Bryer]

I don't know how effective it might be, but you might
consider using the exhaust airflow to suck up the water.


------------------------------------
-->Airflow--> --> Air+Water -->
-----------------/ /----------------
/ /
/ /
Water

I'll think I'll patent that, call it a carburettor maybe.

Older friends will remember the Flit flykiller sprays that worked
just like this - far more ecological (from a material pov only) than
aerosol cans. For a picture see
http://www.packagemuseum.com/packagemuseum/exhibits/flit01/flit01.htm

 

[George R. Gonzalez]

Hi


I thought I'd ask about this. Is it possible to use a conventional
cylinder vacuum cleaner (old sausage dog type) to pump clean water?

No, how silly of you, you can't pump water thru a motor.

But you can of course, pump gasoline.
See your car's gas tank. Or Dave Barry.

 

[N. Thornton]

Hi.


Ian Stirling:

I'd have to say no.
At least certainly no unaltered.

You sure?

The rotor spins at some tens of thousands of RPM.
Even if it could keep this speed when water got to it, it'd be destroyed
by cavitation and general stress, as it's so lightly built.

Lets look at it this way. Water is more viscous, so as water flows
thru it would presumably slow it down and work, at least in that
respect.

Power consumption would go up from motor loading, but then water
cooling would deal with that too, maybe.

Of course there might be a fair bit of power flowing thru the water,
so maybe it'd be warm water coming out the back.

Losses from "windage" due to the close gaps in the motor will be

large.

Right. I guess losses aren't too big a concern in something as barmy
as this


Anthony Wooldridge:

Definite no-no !

You sure? Want me to try it and see? I'll bet you're wrong

Water and air have vastly different viscocity.
Quite apart from the scary water/electricity aspects.

actually that's not hard to deal with. earth the case and you have an
earthed electrode heater.


Regards, NT

PS dont try this at home

 

[John Stumbles]

Older friends will remember the Flit flykiller sprays that worked
just like this - far more ecological (from a material pov only) than
aerosol cans. For a picture see
http://www.packagemuseum.com/packagemuseum/exhibits/flit01/flit01.htm

I have to admit that I'm an older reader and whilst I never saw one of those
pump-type sprays in the flesh (well, metal: you know what I mean) we did
have an attachment for our old Electrolux sausage type vacuum cleaner for
spraying stuff (never sure what stuff: we had the gizmo but I never saw the
instructions or any description for it). It consisted of a glass jar with a
screw-on lid: the lid incorporated a telescopic tube which dipped into the
jar, a socket for the vac hose and a nozzle out of which should emerge what
was being sprayed. The idea was to attach the hose to the blow (exhaust) end
of the vac so the flow of air through the gizmo would create a suction and
draw up liquid from the bottle and spray it out as an aerosol.

Never worked, mind.

 

[anthony wooldridge]

Hi.


Ian Stirling:


You sure?


Lets look at it this way. Water is more viscous, so as water flows
thru it would presumably slow it down and work, at least in that
respect.

Power consumption would go up from motor loading, but then water
cooling would deal with that too, maybe.

Of course there might be a fair bit of power flowing thru the water,
so maybe it'd be warm water coming out the back.


large.

Right. I guess losses aren't too big a concern in something as barmy
as this


Anthony Wooldridge:


You sure? Want me to try it and see? I'll bet you're wrong


actually that's not hard to deal with. earth the case and you have an
earthed electrode heater.

And trip the RCD which stops the pump.
OK you could use an isolating transformer to stop that, (with extreme care)
but when the seal between the motor and pump vanes leak (they are not
designed for water)
you get water in the motor electrics, electrolysis, and corrosion will
eventually stop the motor
if the huge increase in power caused by the presumably low conductivity tap
or worse still dirty water doesn't.
It could last a few minutes if you bypass the RCD. (MTBF 0.1 hrs my
estimate)

Much better to try the wet/dry Vax type with auto empty.

 

[Walter Harley]

I thought I'd ask about this. Is it possible to use a conventional
cylinder vacuum cleaner (old sausage dog type) to pump clean water?
These cleaners work by passing the filterd air stream through the
motor to cool it, so the water would go thru motor as well.

For any unaware person reading this, don't do it as its clearly
dangerous, my question is whether its _possible_?

NT, you've given us a bit of an underspecified problem - thus the ensuing
confusion.

When you say "possible," what do you mean? Do you mean "will it move any
water at all," or do you mean "is this a reliable way to move water," or "is
this a reliable and efficient way to move water," or ...? And, when you say
"clean water," do you mean "clean and relatively ion-free water" or do you
mean "water with no large suspended objects such as seaweed and/or rubber
duckies"?

Of course you can pump clean water with a cylindrical vacuum cleaner, if you
use it as a piston within some larger cylinder with appropriate valves. But
I assume that's not what you mean.

 

[Roger Lascelles]

Interestingly, a choked off vacum cleaner draws much less power than a free
running one ! If you block the pipe, you will hear that the motor runs
*faster* - showing that the load is less.

This is due to the characteristics of centrifugal pumps - you can look it up
in an engineering encyclopedia or handbook - or I'll bet there is info on
the web.

Possibly, the choked off cleaner may overheat because the motor still
consumes power and has almost zero airflow.

At work we have a solder fume extractor rigged up from a barrel vac hooked
up to a solder iron tip extractor. Very little air flows into the cleaner
through the small diameter tip pipe, yet the cleaner runs for minutes and
has never failed.

Roger

 

[Roger Lascelles]

I remember my Dad in the 1960s spraypainting with one of those vacum cleaner
attachments. It really did work for him. You put your finger over an air
hole to start spraying. I wonder if its still in the garage at Mum's place
?

Roger

 

[Ian Buckner]

water?


No, how silly of you, you can't pump water thru a motor.

But you can of course, pump gasoline.
See your car's gas tank. Or Dave Barry.

You can pump gasoline, however make _very_ sure you don't get down to
vapour!
Many years ago one of our guys wanted to get the fumes out of a car
gas (petrol)
tank using a vaccuum cleaner before welding a leak. The brush sparking
ignited
the fumes, he lost most of his beard and eyebrows. Took him years to
live it down.

Regards
Ian

 

[a]

It should work too, isnt that how most airbrushes still work today (although
maybe the air source isnt from a vacuum cleaner any more

 

[N. Thornton]

Hi


The challenge is on!

And trip the RCD which stops the pump.

What RCD? Plenty of places don't have one. For this experiment its a
location with no RCD, of any kind.

OK you could use an isolating transformer to stop that, (with extreme

care)

lol, I dont think it would be extreme care trying anything like this

but when the seal between the motor and pump vanes leak (they are not
designed for water)
you get water in the motor electrics, electrolysis, and corrosion will
eventually stop the motor

ah no, you misunderstand, its worse than that. In cylinder vacs all
the air pumped by the impellor goes straight thru the motor to cool
it. Not around it, thru it. That's how they use such small high power
motors. So if one is used for pumping, the water goes right thru the
motor mechanics and electrics from minute one.

if the huge increase in power caused by the presumably low conductivity tap
or worse still dirty water doesn't.
It could last a few minutes if you bypass the RCD. (MTBF 0.1 hrs my

estimate)

We got a 500 watt motor on a 30A fuse, 240v ring main. There is the
question of just how much power would flow thru the water, I don't
know. I spose if we dip most of the mains lead in the water we could
at least cool that too. After all its only 2A rated.

No, how silly of you, you can't pump water thru a motor.

Hehe, how much you want to bet? I say it can be done. And I'm wililng
to post practical results.

NT, you've given us a bit of an underspecified problem - thus the ensuing
confusion.

When you say "possible," what do you mean? Do you mean "will it move any
water at all," or do you mean "is this a reliable way to move water," or "is
this a reliable and efficient way to move water," or ...?

I simply mean is it possible - not is it reliable, safe and sensible,
just possible. And not for 3 seconds, but possible to empty the whole
1000 gallon tank. That's about 4.5 tonnes of rainwater. So I expect
it'll need to run for more than 0.1 hours.

And, when you say
"clean water," do you mean "clean and relatively ion-free water" or do you
mean "water with no large suspended objects such as seaweed and/or rubber
duckies"?

A big tank of rain water sitting next to a house. So, barely clean, no
ducks anyway. Certainly not ion free.

Of course you can pump clean water with a cylindrical vacuum cleaner, if you
use it as a piston within some larger cylinder with appropriate valves. But
I assume that's not what you mean.

Hehe. What I mean is by plugging it in the mains and sticking the
nozzle in the water. The really stupid way.


Well no-one's convinced me I can't do it yet

In case anyone's tempted, NEVER try this dangerous idea at home. Its
really stupid.


Regards, NT

 

[Mark Zenier]

I don't know how effective it might be, but you might
consider using the exhaust airflow to suck up the water.
------------------------------------
-->Airflow--> --> Air+Water -->
-----------------/ /----------------
/ /
/ /
Water
I'll think I'll patent that, call it a carburettor maybe.

aspriator, FYI.

Mark Zenier [email protected] Washington State resident