Choosing a Vacuum Pump for your laboratory

Vacuum pumps are found in many laboratories having a wide range of uses such as filtration, freeze-drying, evaporation and concentration amongst other uses. They come in a variety of sizes and functionality which can prove daunting to decide which is right for you particular use or is it uses?

Laboratory Vacuum PumpsLaboratory Vacuum Pumps

How do you decide which pump is best suited for the task(s)?

Laboratory vacuum pumps can have a lot of different features, which makes them suitable for different jobs.
For example, “chemical duty” pumps have better chemical resistance, for working with organic solvents or corrosive substances. Others can apply pressure as well as vacuum, while some are oil-free to reduce maintenance requirements and the risk of contamination. Some pumps are available with a regulator or gauge to accurately monitor the vacuum, then there is the flow rate and ultimate vacuum to consider, to ensure the pump is powerful enough for the job. In addition, there are four main types of vacuum pumps to choice from:

  • Rotary Vane
  • Diaphram
  • Combination pump
  • Scroll

At Camlab we supply rotary vane and diagram pumps from two main suppliers KNF and Welch by Garnder Denver. Both these types are widely used in laboratories. Below we have provided some common uses example of pumps.

But first, let us look at some key points to consider:

Where is the pump to be stored is it bench top or under bench?

 May be limited by pump size and acceptable noise levels.

How about pressure required?
  • Common pressures required would be between 200 to 10-3 mbar - rotary vane, and diagram pumps will suit this purpose.
  • If you are working on atomic physics, field emission microscopy or x-ray photoelectric spectroscopy you would be looking for working pressure between 10-3 to 10-9 mbars, of these applications specialist pumps would be needed such as diffusion, ion or triple molecular pumps would be options
What chemicals are you working with?
  • Solvents?
    • Low boiling point? i.e. acetone, methlyene chloride -- less vacuum
    • High boiling point? i.e. water -- stronger vacuum
Flow capacity?

Choose one that suits your needs too low or too high will prove problematic to control effectively. This will assist you in determining pump size.

Vacuum control?

 Options include manual, two-point or adaptive vacuum controls

Oil-free?

Diaphragm pumps would suit this purpose.

Noise?

Will this be an issue is there as set range that is requried

Cost is this a concern?

Diaphragm pumps can provide the most cost-effective option