Sciencemadness Discussion Board

Too powerful vacuum pump..

chucknorris - 7-12-2012 at 03:31

I bought a vacuum pump that is a little too harsh for me. Even liquids with BP at 200C will boil at room temp, so I need to decrease the power a little so that those could be handled without dealing with special coolrants. Should I just leave the tubings a little loose for intentional leaks or are there other methods?

kavu - 7-12-2012 at 06:16

An easy way to achieve pressure control is to hook up the vacuum line with a three-way adapter to a valve. The more you open the valve, the higher the pressure. Using a simple straight glass stopcock has worked rather well for me.

chemrox - 7-12-2012 at 13:56

please see https://www.sciencemadness.org/whisper/viewthread.php?tid=21...
where the various methods of controlling vacuum are discussed. Please also read up on how to build a vacuum line. A lot needs to be done to protect the pump, read and maintain the vacuum. There's some material in Vogel's 3rd and a couple of books by Gary S Coyne.

zed - 7-12-2012 at 14:24

Too powerful a vacuum? You should dispose of such a pump immediately. Very dangerous.

Just leave it out next to your garbage cans, and as a friend, I'll come over and haul it away. For you, I charge nothing.

chemrox - 7-12-2012 at 17:50

Quote: Originally posted by zed  
Too powerful a vacuum? You should dispose of such a pump immediately. Very dangerous.

Just leave it out next to your garbage cans, and as a friend, I'll come over and haul it away. For you, I charge nothing.


This was my alternate reply hehehehe

m1tanker78 - 7-12-2012 at 17:55

Quote: Originally posted by chucknorris  
I bought a vacuum pump that is a little too harsh for me.


Harbor Freight??

Tank

chucknorris - 7-12-2012 at 22:37

Nope, from the internets. :D Just cant hold the liquids between 100-300c Im intending to boil and Im not gonna use highly expensive dry ice, although even it wont help when distilling substances at the lower 100C's scale.

I will give a try for that injection needle leak. I just need to regulate the pressure up to the millibar scale(5mbar is more than enough for just about all applications I do, and my pump goes to 50 microbars). An insulin needle should do the trick. :P

[Edited on 8-12-2012 by chucknorris]

sargent1015 - 7-12-2012 at 22:42

Quote: Originally posted by chucknorris  
highly expensive dry ice,
[Edited on 8-12-2012 by chucknorris]


Wait... What? Expensive???? It's like $1/pound!

chucknorris - 7-12-2012 at 22:59

In my country it costs 15 euros per kg + delivery costs which force you to order at least some 30kg to make the price even remotedly bearable.

[Edited on 8-12-2012 by chucknorris]

Lambda-Eyde - 7-12-2012 at 23:40

Quote: Originally posted by sargent1015  

Wait... What? Expensive???? It's like $1/pound!

Yeah, and a sixpack of beer is 5$!

(do you see how ridiculous my statement is?)

sargent1015 - 8-12-2012 at 00:40

Quote: Originally posted by chucknorris  
In my country it costs 15 euros per kg + delivery costs which force you to order at least some 30kg to make the price even remotedly bearable.

[Edited on 8-12-2012 by chucknorris]


Well I can walk down to the grocery store and pick it up for that cheap...

As for a 6-pack, well that's only $7

nachra - 12-1-2013 at 17:58

Miller highlife is only 5$ if u consider that booze

hyfalcon - 13-1-2013 at 03:30

Budweiser is $14.00 an 18 pack here. Dry ice is $1.65/lb.

Darkblade48 - 13-1-2013 at 18:11

And here I am paying $30.50 for an 18 pack of Budweiser....

sargent1015 - 13-1-2013 at 22:45

Why do you guys drink that stuff?? :P

Anyways, back on topic, dry ice can be had at reasonable prices!!

Lambda-Eyde - 15-1-2013 at 02:03

Quote: Originally posted by sargent1015  
Why do you guys drink that stuff?? :P

Anyways, back on topic, dry ice can be had at reasonable prices!!


It should be said that both Budweiser and Miller are undrinkable and a fucking disgrace to anything called beer, but that's not really my point. My point is that I pay ~25$ for a sixpack of mediocre lager beer here in Norway, the difference between the two of us is that I am the only one who seem to understand that this is no universal truth.

For half a liter of strong craft beer, I pay ~10$ and once I paid ~60$ for a bottle of Black Tokyo* Horizon at a pub in Oslo, which was well worth it. And if I want dry ice, it's on the order of ~15$/kg, 8 kg minimum order, and a few days order time.