BW-704 100mL Diffusion Pump Oil


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BW-704 Diffusion Pump Oil

Beaker & Wrench® highly recommends using BW-704 Oil for your Diffusion Pump!

BW-704 Diffusion Pump Oil will keep your diffusion pump clean of carbon and tar buildup. BW-704 is thermally and chemically stable. Colorless and silicone-based, BW-704 Diffusion Pump Oil offers an impressive pump-down and is manufactured for higher vacuums of 10E-6 to 10E-8 (unwrapped) or 10E-10 to 10E-11 (trapped). BW-704 diffusion pump oil also offers resistance to radiation, explosion and oxidation as it maintains a high boiling point. While most diffusion pump oils cannot handle exposure to air, BW-704 can when operating temperatures are active.

If operating a diffusion pump bought from Beaker & Wrench®, the suggested amount of diffusion pump oil to use is 100ML. To attain optimal functionality, Beaker & Wrench® recommends changing the diffusion pump oil every 1-3 months (varies depending on usage) or when diffusion pump does not hold proper vacuum.

When changing diffusion pump oil, disconnect pump entirely to ensure pump is OFF and cool to touch. Pour discarded diffusion pump oil out of top port; this will be darker in color. If there are particulates in the diffusion pump, this means the oil should have been changed sooner. Keep a data log regarding when the diffusion pump oil is changed to assure this occurs in a timely manner. If there is tar/particulates in the discarded oil, wash the tank out with water a few times. If available, use compressed air to dry the tank; otherwise wait for the tank to dry in full. Make sure proper PPE is being used, such as eye protection. When finished, pour 100ML BW-704 into side port of diffusion pump and reconnect your diffusion pump to unit.

Spec Sheet

Specifications: BW-704 Diffusion Pump Oil 
Color Transparent 
Ultimate Vacuum (untrapped) 10E-7 to 10E-8 torr
Extrapolated Vapor Pressure 2 x 10E-8 torr
Specific Gravity at 25°C 1.07
Viscosity at 25°C 39 cSt
Flash Point (open cup) 221°C
Boiling Point (at 0.5 torr) 215°C
Hazardous Ingredients None
Chemical Profile Tetramethyltetraphenyl-Trisiloxane