Welch WOB-L Pump 2561
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Manufacturer: Welch Vacuum - Gardner Denver

Welch WOB-L Pump 2561

SKU: 2561B-50

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 Welch WOB-L Pump 2561

***Note: This item has a possible lead time of 2-3 weeks depending on stock availability.***

Reliable WOB-L Piston pump is perfect for many common laboratory vacuum applications. Features: Vacuum to 5 Torr (29.8"Hg). Includes Vacuum Regulator and Gauge - simple to adjust and monitor vacuum level. Inlet Water Trap - float ball rises to seal off pump from accidental ingestion of water. Muffler quiets pump and filters discharge air. For use with dry or aqueous vapor applications only.


  • Economical
  • Oil Free
  • Adjustable Vacuum


Vacuum Filtration

  • Many filtrations require only minimal vacuum to proceed; deep vacuum is not required. Vacuum pump flow required is roughly proportional to the total surface area of filters being used. Filtration of particulate-clogging samples can be improved somewhat with deeper vacuum, but a combination of larger filter surface area, smaller samples, and sequential use of decreasing porosity filter papers may also be required for timely filtration. Choose a standard duty vacuum pump for aqueous vapors; use a PTFE pump for resistance to harsh chemicals. 


Applications Vacuum filtration up to 6 funnel manifold; Lab automation - aspiration of systems utilizing 96 / 256 well format; Welchnet lab installations up to 10 outlet fixtures (geneneral use, filtration)
Type Laboratory Vacuum Pump
Free Air Displacement cfm (l/min.) @60Hz 3.5(100)
Free Air Displacement m3/hr (l/min.) @50Hz 4.9(83)
Ultimate Pressure 60(80)
Maximum Vacuum 27.6
Max Pressure PSIG (pascal)
Motor Horsepower (watts) 1/3(250)
Adjustable Vac. / Gas Ballast Yes
Tubing Needed 1/4(7)
Intake Thread NPT 1/4
Overall Dimensions LxWxH in. (cm) 15.0x10x10 (38.1x25.4x25.4)
Ship Weight 24(10.9)
Shipping Carton Dimensions LxWxH in. (cm) 21x12x15 (53x30x38)
Intake Catch Jar Yes
Adjustable Vacuum Knob
Vacuum Gauge Dial