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Built for Demanding Lab and Industrial Applications

If you're running vacuum processes that require consistent performance, low maintenance, and oil-free operation, the WOB-L Piston Pump Model 2581B-50 from Welch Vacuum is designed to meet those needs. This pump delivers up to 74 L/min (2.6 CFM) and reaches an ultimate vacuum of 60 Torr, making it suitable for filtration, aspiration, degassing, and other mid-range vacuum tasks.

Its compact footprint and quiet operation make it a fit for benchtop use, while the rugged design supports continuous duty cycles. The pump is oil-free, reducing contamination risk and simplifying upkeep—ideal for labs that prioritize clean environments and low operating costs.

Full Product Manual

The official product manual includes installation instructions, performance specs, maintenance schedules, troubleshooting guidance, and part diagrams

Key Specifications

FeatureValue
Model2581B-50
Flow Rate74 L/min (2.6 CFM)
Ultimate Vacuum60 Torr
Motor1/3 HP, 115V, 60Hz
Noise Level~50 dB (A)
Weight18.6 kg (41 lbs
Port Size3/8" NPT
Pump TypeOil-free WOB-L piston

 

Common Use Cases

 

  • Filtration and aspiration in biological and chemical labs
  • Degassing liquids in analytical workflows
  • Vacuum drying of small samples
  • Vacuum ovens and desiccators
  • Environmental testing setups

FAQs

Minimal. Replace inlet filters periodically and inspect diaphragm and piston seals annually. The pump is oil-free, so no fluid changes are needed.