Non-Chemical Filtering Flask

[Anonymous]

Question, how many inches of vacuum will the pyrex flask sustain before imploding.

I'm using my vacuum pump used for refrigeration work which pulls a good 30 Hg, the flask is a 4 liter with 1 liter Buchner filter, under vacuum you can see the liquids boil at room temperature.

My concern is should the filter become so impregnated with fines that the vessel inside vacuum should increase to the point it would implode.

Thanks.

ttys
Gustavus

 

[Lou]

You can take them to full vacuum without any worry of implosion. I use a KNF Neuberger that pulls to ~1 torr and it's fine!

Keep in mind that the pressure differential between 1 torr and 0.001 torr isn't much with respect to the force exerted by the atmosphere against the glass.


Lou

 

[Anonymous]

Lou is absolutely correct . As long as there are no "star cracks" (these are visible imperfections or minute cracks" then there is no danger of implosion. It is worthwhile to occassionaly inspect the flask though.

 

[goldsilverpro]

Lou is always right. It's great to have his knowledge available to us.