Vacuum Pump Oil

[Ernest Figueroa]

I have an old Welch Duo Seal Vacuum Pump that is in dire need of new vacuum pump oil. What is the deal on vacuum pump oil and can something else be substitituted and provide better operation?

thanks

 

[TooManyWheels]

I used to hang out at the alt.hvac newsgroup, and while I don't remember much of the specifics, I do remember that vacuum pump oil is specific to the application in terms of weight, ability to interact with refrigerant, resist water, etc.

As you might expect, it doesn't make much sense to experiment with something not designed for the application.

 

[labman]

Surely you don't need that much so that price shouldn't be a big
factor. Availability of real vacuum pump oil could be a problem. I
ran across this link, http://www.sciencelab.com/.

If that doesn't help and you have to use something else, maybe a
straight weight oil. Volatility is a big issue with vacuum pump oil. If
you can figure the right viscosity, then check the volatility specs of
different oils in that range. I would expect a 30 weight oil to have a
lower vapor pressure than a 10W-30.

 

[Ernest Figueroa]

Thanks for the link guys. i found some at a dot com that sells parts for automotive airconditioning and such. It is really inexpensive, but it is not something you find at walmart.

 

[bheinz57]

You can always look up certain manufacturers and see what they recommend. At work we use synthetic in our vacuum pumps, whether they are for medical air or just recovering refrigerant. See Robinaire/Becker for some more info. Brian

 

[416Rigby]

Go to www.lesker.com .Kurt Lesker carries everything related to UHV.

 

[lobo11]

I use similar Welch pumps at work, we use a Vac. Pump oil Distributed by VWR Scientific. I think a straight weight oil would work well. I will list the specs. given on the pump oil we use here so you can find a comparable oil at a good price.
Fpash Point-415
Fire Point-472
Visc, SUS @ 100F--248
Visc, SUS @ 210F--51
PP-5F

McMaster-Carr also sells Vaccum Pump Oil in gallon and 5 gallon containers, they are on-line.

 

[davefr]

I had a similar problem finding it locally.

I'd suggest Grainger Industrial. They have branches in most major cities.