Sciencemadness Discussion Board

Vacuum Pump Question

chelu55 - 10-11-2013 at 20:10

Hey everyone,

I am conducting a study to evaluate the elasticity of rubber stoppers on drug vials after multiple needle punctures. However, I have not done this experiment before and the protocol requires me to reduce the vacuum chamber pressure to 27 kPa (~4 psi). Any advice on they best type vacuum approach?

After researching vacuum pumps I think a water aspirator will not produce enough pressure. Correct? If so, my next thought is purchasing as vacuum pump. However, these cost hundreds of dollars. Does anyone have any insight on the best vacuum method to reach pressures of 27 kPa? Any help is appreciated. Thanks!

Magpie - 10-11-2013 at 21:36

If your tap water is reasonably cold you should be able to pull a vacuum down around 1 psi. Or:

http://www.harborfreight.com/25-cfm-vacuum-pump-98076.html

chelu55 - 11-11-2013 at 02:59

Thanks Magpie! Looks like the vacuum pump is the way to go. I appreciate your help!

Dr.Bob - 11-11-2013 at 08:37

You could buy a diaphram pump from Ebay for a few hundred that might work fine. They are ideal for that PSI range if you don't need a lot of flow. Gast, KNF, vacumbrand, and others are all fine, but buy one that is promised to be working, and not cheap kit.

http://www.ebay.com/sch/i.html?_trksid=p2050601.m570.l1313.T...