KNF N920G High-Performance Chemically Resistant Diaphragm Vacuum Pump

Overview

The KNF N920G is a high-integrity, oil-free diaphragm vacuum pump engineered for demanding laboratory environments where chemical resistance, long-term reliability, and precise vacuum control are critical. Based on KNF’s proven 9-series diaphragm technology, the N920G operates on positive displacement principles using PTFE-coated elastomeric diaphragms and chemically inert valve assemblies—enabling stable, pulse-free vacuum generation without lubricants or hydrocarbon contamination. Its ultimate vacuum of 2.0 mbar (5 mbar with gas ballast valve engaged) and free air flow of 21 L/min make it suitable for continuous operation across a wide range of vacuum-dependent workflows, including solvent removal, vacuum drying, and as a backing pump for turbomolecular or diffusion pumps. Designed and manufactured in Freiburg, Germany, the N920G adheres to IEC 61000-6-3 (EMC) and IEC 61000-6-2 (immunity) standards, and its construction complies with RoHS and REACH directives.

Key Features

• Chemically resistant wetted path: PTFE-coated diaphragms, EPDM or Viton® valves, and stainless steel (AISI 316) pump head components ensure compatibility with acidic, basic, and organic vapors—including HCl, HF, acetic acid, THF, and dichloromethane.
• DC inverter-driven motor with analog speed regulation: Enables stepless adjustment of rotational speed (and thus pumping speed) via front-panel rotary potentiometer—supporting optimized process control and energy efficiency during variable-load applications.
• Integrated gas ballast valve: Allows controlled admission of ambient air to prevent condensate buildup in the pump chamber when handling high-vapor-pressure solvents, extending service life and maintaining performance stability.
• Low-vibration, quiet operation: Vibration < 1.2 mm/s RMS at 50 Hz; sound pressure level ≤ 52 dB(A) at 1 m—designed for integration into laminar flow hoods, gloveboxes, or shared lab spaces without acoustic interference.
• Robust mechanical architecture: Reinforced aluminum housing, precision-machined mounting interfaces, and IP20-rated electrical enclosure ensure durability under daily laboratory use and compliance with IEC 60529 ingress protection requirements.

Sample Compatibility & Compliance

The N920G is validated for use with corrosive, condensable, and non-reactive process gases and vapors commonly encountered in analytical, synthetic, and materials science laboratories. It meets ISO 8573-1:2010 Class 0 for oil-free air quality—certified for applications requiring zero hydrocarbon carryover. While not intrinsically safe, its design supports integration into systems compliant with ATEX Zone 2 (gas) and IECEx requirements when installed with appropriate isolation and venting. The pump is routinely deployed in GLP- and GMP-regulated environments where audit-ready documentation (e.g., Factory Acceptance Test reports, material certificates per EN 10204 3.1) is available upon request.

Software & Data Management

The N920G operates as a stand-alone analog-controlled instrument and does not include embedded digital communication interfaces (e.g., RS-485, Modbus, or Ethernet). However, its analog speed input (0–10 V DC) enables seamless integration into centralized lab automation platforms via programmable logic controllers (PLCs) or SCADA systems. For traceability in regulated settings, users may log operational parameters—including runtime hours, speed setpoints, and thermal status—using external data acquisition modules compliant with FDA 21 CFR Part 11 requirements (e.g., electronic signatures, audit trails, and secure data export).

Applications

• Rotary evaporation and fractional distillation under reduced pressure
• Vacuum-assisted gel drying, lyophilization support, and desiccation of moisture-sensitive samples
• Gas sampling and solid-phase extraction (SPE) manifold evacuation
• Backing pump for high-vacuum systems (e.g., mass spectrometers, electron microscopes, thin-film deposition tools)
• Replacement for water aspirators and oil-sealed rotary vane pumps—eliminating wastewater disposal, oil maintenance, and hydrocarbon contamination risks

FAQ

Is the N920G suitable for continuous duty cycles in a 24/7 analytical lab environment?
Yes—the N920G is rated for continuous operation at ambient temperatures up to 40 °C and features thermally protected motor windings and automatic thermal shutdown (resettable via power cycle) to prevent overheating under sustained load.
Can the pump handle saturated solvent vapors without performance degradation?
When used with the gas ballast valve open, the N920G tolerates intermittent exposure to saturated vapors of low-boiling solvents (e.g., diethyl ether, pentane); however, prolonged exposure to >80% relative saturation may reduce diaphragm service life and requires scheduled inspection per KNF Maintenance Schedule M-920G Rev. 3.
Does KNF provide calibration or performance verification documentation?
KNF supplies a Factory Performance Certificate with each unit, including measured ultimate vacuum, free-air flow, and noise/vibration test results traceable to DAkkS-accredited metrology labs. On-site calibration services are available through authorized KNF Service Partners in EMEA, North America, and APAC regions.