Vacuum Pump Performance

If this isn't homework, why not talk to whomever built the pump.

If you are going to purchase a pump, talk to the potential suppliers.

Good luck.

PS If this is homework, you might start by looking at the gas laws.

It sure does sound like a homework problem, which we are not inclined to answer, but rather "nudge" or "guide" the OP in the right direction.

Here are some resources which may help you discover the answers yourself:

http://www.engineeringtoolbox.com/vacuum-evacuation-time-d_844.html

http://lpc1.clpccd.cc.ca.us/lpc/tswain/chapt3.pdf

http://www.hydraulicspneumatics.com/200/TechZone/Vacuum/Article/True/6460/TechZone-Vacuum

Many more can be found using a simple web search with the right terms.

Good luck!

While this does sound like a homework problem, vacuum pumping problems are not trivial problems. If one has a simple pristine vacuum chamber surfaces and the pressure lower limit keeps the pumping calculation as still just a simple differential equation then this maybe something that people can calculate. But think about what will happen if 10 mL of liquid water starts off inside the vacuum chamber in a test tube. One can get fooled into thinking that the water vapor pressure of water at 25°C of 23.8 mm-Hg (aka 23.8 torr) will not come into play at 60 torr that the OP mentioned but this is not the case. The water vapor pressure will be a partial pressure source that will continue to provide water at 23.8 torr until all of the water vaporizes.

Hello!

To calculate the time to achieve required vacuum is depends upon following equation:

Pump flow rate(M³/hr) = [V (m³) X Ln (Pi / Pf)] / T (hrs)

Where Pi is the initial pressure (May be atmospheric pressure in your case) and Pf is the final pressure you wanted to achieve.

Ln is the natural logarithm.

V is the flow capacity of vacuum in m³

T is the time required to achieve the Pf vacuum.

I hope that you will find this in line to your requirement.

With best regards,

Prasad Dayal