The Welch Direct Drive High Vacuum Pump 8925A is ideal for use with the Shel Lab Model VPX9 Series 9.0 cubic foot capacity Vacuum Oven as well as a variety of laboratory applications.
For many applications, Welch Dry Vacuum Pumps will provide drying speeds equal to those of traditional, oil-seal pumps. This means you can upgrade to a cleaner vacuum pump that is easier to maintain.
Suitable samples include: Foods (Nuts, Cheeses, Fruits, etc), Cosmetics, wet or surface-coated samples needing moisture dryoff, chemicals drying, solvent evaporation, and many others. If your samples can be processed at 3 torr – 10 torr pressure levels, a dry pump will work well in 0.67 cubic foot, 1.7 cubic foot, and even 4.5 cubic foot capacity Shel-Lab Vacuum Ovens.
For electronic component bakeout, curing, or other samples requiring pressures of 1-3 torr, Welch Chemstar, DuoSeal (Belt Drive) and Direct Drive Oil-Seal High Vacuum Pumps are excellent choices for all size vacuum ovens.
Vacuum system configuration with a cold trap is recommended for use with harsh chemicals. Direct drive pumps are not recommended for filtration, aspiration, drying electrophoresis gels, or other applications requiring sustained operation above 30 torr.
High Vacuum; 4x10-4 torr (5x10-4 mbar)
Advanced design with fewer parts
Rugged, compact, quiet
General Vacuum Work
Annular Spaces / Transfer Lines
Free Air Displacement
CFM (L/min) @ 60Hz
(L/min) m3/hr @ 50Hz
Ultimate Pressure (Torr)
4 x 10 -4
Motor/Pump Speed (60Hz)
Motor Horsepower (watts)
Oil Capacity, qt. (liters)
Tubing Needed, I.D. in.5
Weight, lbs (kg)
Dimensions L x W x H in. (cm)
1.2 x 7.1 x 10.7
(53.8 x 17.9 x 27.2)
Ship Weight, lbs (kg)
Shipping Carton Dimensions
L x W x H in. (cm)
29 x 11.5 x 15.5
(73.7 x 29.2 x 39.4)
Wired for 115V, 60 Hz, 1 PH with N. American 115V Plug
Some motors have extended voltage ranges. All single phase motors have overload protection. For explosion proof, TEFC, 3 Phase and others, consult price list.
115V, 60Hz models are CSA approved.
230V, 50Hz models are CE marked.
Two-stage pumps should not be operated continuously at pressures above 10 Torr.
Exhaust filters not included. See Accessories - Exhaust filters for selection.