KNF N950.50 High-Performance Diaphragm Vacuum Pump

Overview

The KNF N950.50 is a high-efficiency, oil-free diaphragm vacuum pump engineered for demanding laboratory and light industrial applications where chemical compatibility, long-term reliability, and precise vacuum control are critical. Based on KNF’s proprietary 9-series diaphragm technology, the N950.50 employs a multi-stage, hybrid series-parallel pumping architecture to deliver robust performance across a wide operating range — achieving an ultimate vacuum of 2.0 mbar and a maximum free-air flow rate of 55 L/min at ambient pressure. Unlike oil-lubricated or water-ring systems, this pump operates entirely without lubricants, eliminating the risk of sample contamination, oil backstreaming, or wastewater generation. Its brushless DC motor with integrated frequency control enables smooth, stepless speed regulation — allowing users to dynamically match pumping capacity to process requirements while minimizing energy consumption and acoustic emissions (≤52 dB[A]). Designed and manufactured in Freiburg, Germany, the N950.50 reflects KNF’s commitment to precision engineering, material science rigor, and sustainable laboratory infrastructure.

Key Features

• Proprietary KNF 9-series reinforced diaphragm assembly for extended service life (>15,000 hours typical MTBF) and consistent volumetric efficiency
• Brushless DC motor with closed-loop speed control: enables real-time adjustment of flow rate (0–100% of nominal speed) and optimized energy use
• Fully oil-free operation with chemically resistant wetted materials: PP housing, PTFE-coated diaphragms, and FPM valve plates — compatible with organic solvents, acids, and bases per ISO 15141 corrosion classification
• Low-vibration mechanical design with elastomeric mounting interface — suitable for integration into sensitive analytical platforms (e.g., mass spectrometry pre-vacuum stages)
• Compact footprint (115 × 116 × 183 mm) and lightweight construction (7.4 kg) for benchtop flexibility and mobile system integration
• Integrated thermal protection and electronic current limiting — compliant with IEC 61000-6-2/6-4 EMC standards

Sample Compatibility & Compliance

The N950.50 is validated for continuous duty in vacuum applications involving aggressive vapors and condensable media, including acetone, ethanol, ethyl acetate, HCl(aq), and dilute nitric acid — provided appropriate gas ballast (if required) and optional exhaust filtration are implemented. All wetted components meet USP Class VI biocompatibility requirements and comply with FDA 21 CFR 177.2470 for food-contact polymers. The pump carries CE marking under the EU Machinery Directive 2006/42/EC and Electromagnetic Compatibility Directive 2014/30/EU. It is UL Recognized (E337529) for use in North America and conforms to RoHS 2011/65/EU restrictions on hazardous substances. For GLP/GMP environments, its stable vacuum output supports reproducible method transfer in ASTM E2910 (vacuum drying) and ISO 29561 (rotary evaporation validation) protocols.

Software & Data Management

While the N950.50 operates as a standalone analog device, it features a 0–10 VDC analog input for external speed command and a 0–10 VDC analog output proportional to actual motor speed — enabling seamless integration into LabVIEW, DeltaV, or Siemens S7 PLC-controlled workflows. Optional KNF Digital Interface Module (DIM-N950) adds Modbus RTU (RS-485) communication, real-time status reporting (temperature, current, runtime), and configurable alarm thresholds (e.g., overtemperature, overload). Audit-trail-capable logging is supported when paired with KNF’s certified data acquisition software (KNF PumpControl v3.2), which complies with FDA 21 CFR Part 11 requirements for electronic records and signatures when deployed on validated Windows OS platforms.

Applications

• Primary vacuum source for rotary evaporators (up to 5 L scale) and vacuum concentrators in pharmaceutical QC labs
• Pre-vacuum stage for turbomolecular and cryogenic pumps in surface analysis (XPS, AES) and high-vacuum coating systems
• Vacuum drying of gels, hydrogels, and lyophilized biologics in R&D settings (per ISO 13485 Annex C)
• Gas evacuation in glove boxes, desiccators, and solvent recovery units handling halogenated or polar organics
• Replacement for water aspirators in environmentally regulated facilities — eliminates water waste and sewer discharge liabilities
• Process vacuum for membrane filtration, degassing of resins, and vacuum-assisted resin transfer molding (VaRTM)

FAQ

What is the recommended maintenance interval for the N950.50?
Routine inspection every 6 months is advised; diaphragm and valve replacement is typically required after 10,000–15,000 hours of operation under standard conditions — documented in KNF’s Maintenance Logbook (Ref. MNL-N950-EN).
Can the N950.50 handle condensable vapors from rotary evaporation?
Yes — when used with KNF’s optional cold trap (CT-200) and activated carbon filter (AF-100), it maintains stable performance with up to 30% vapor load by volume; consult KNF Application Note AN-087 for solvent-specific derating curves.
Is the pump suitable for cleanroom environments?
It meets ISO Class 5 (Class 100) particle emission limits when equipped with KNF’s HEPA-exhaust filter kit (EF-HEPA-N950) and operated at ≤60% speed to minimize particulate shedding.
Does KNF provide calibration certificates traceable to NIST or DAkkS?
Yes — factory calibration reports (including flow vs. vacuum curve, ultimate pressure verification, and sound pressure level measurement) are available upon request and are traceable to PTB (Physikalisch-Technische Bundesanstalt) standards.
How does the N950.50 compare to the N920G20 in terms of duty cycle capability?
The N950.50 is rated for continuous 100% duty cycle at 2.0 mbar; the N920G20 is limited to 30-min intermittent operation under identical vacuum conditions per KNF Technical Bulletin TB-920-EN.