KNF N840.3FT.18 Chemically Resistant Diaphragm Vacuum Pump

Overview

The KNF N840.3FT.18 is a high-performance, chemically resistant oil-free diaphragm vacuum pump engineered for demanding laboratory applications requiring both corrosion resilience and operational reliability. Based on KNF’s proven dual-head diaphragm architecture, it generates vacuum via positive displacement through elastomeric PTFE-coated diaphragms actuated by precision-machined eccentric shafts—eliminating lubricants, oil vapor contamination, and mechanical wear associated with rotary vane or piston technologies. Its ultimate vacuum of 8 mbar and continuous flow rate of 34 L/min at atmospheric inlet pressure make it especially suitable for integration with small- to medium-capacity rotary evaporators (≤5 L), vacuum drying ovens, gel dryers, and reduced-pressure distillation setups where chemical inertness and long-term unattended operation are critical.

Key Features

• Chemically inert wetted materials: PTFE pump head, PTFE-coated diaphragms, and perfluoroelastomer (FFPM) valves ensure compatibility with aggressive vapors including concentrated acids (e.g., HCl, HNO₃), bases (e.g., NaOH), solvents (e.g., acetone, THF), and halogenated compounds.
• Oil-free, maintenance-free operation: No lubrication required; no oil changes, filter replacements, or valve reseating under normal use—reducing total cost of ownership and eliminating risk of sample contamination.
• Dual-head configuration: Enhances flow stability and extends service life by balancing mechanical load and thermal distribution across two synchronized pumping chambers.
• Low-noise and low-vibration design: Acoustic emission <52 dB(A) at 1 m distance; vibration amplitude <1.2 mm/s RMS—enabling placement on shared lab benches without interfering with sensitive instrumentation (e.g., balances, microscopes).
• Continuous-duty rated motor: 1 kW brushless AC motor with integrated thermal monitoring and automatic shutdown protection ensures safe 24/7 operation without duty-cycle limitations.
• Compact footprint: Dimensions of 341 × 226 × 166 mm allow seamless integration into fume hoods, under-bench cabinets, or mobile lab carts.

Sample Compatibility & Compliance

The N840.3FT.18 is validated for handling corrosive, condensable, and particulate-laden process gases commonly encountered in synthetic chemistry, pharmaceutical development, and polymer characterization workflows. It complies with IEC 61000-6-3 (EMC emission standards) and IEC 61000-6-2 (immunity). While not intrinsically safe, its construction meets general laboratory safety requirements per EN 61010-1. The pump is compatible with GLP and GMP environments when deployed with documented preventive maintenance logs and calibration traceability—particularly relevant for USP analytical instrument qualification (AIQ) frameworks. It serves as a direct replacement for water aspirators in solvent recovery systems, reducing wastewater generation and energy consumption associated with chilled water circulation.

Software & Data Management

This analog-controlled pump does not feature digital interfaces or embedded firmware. However, its robust analog architecture ensures electromagnetic compatibility in electromagnetically noisy laboratory settings (e.g., adjacent to NMR spectrometers or RF sources). For automated systems, the unit can be integrated via external relay control (24 V DC trigger input available on optional control box) or pressure-switch feedback loops. When used with third-party vacuum controllers (e.g., Vacuubrand VACUU·SELECT or KNF’s own EC-100 series), real-time pressure regulation, ramped evacuation profiles, and event-triggered logging become feasible—supporting audit-ready data capture aligned with FDA 21 CFR Part 11 principles when paired with compliant software platforms.

Applications

• Rotary evaporation of acid-sensitive or base-labile compounds (e.g., ester hydrolysis, peptide coupling)
• Vacuum drying of hygroscopic or oxidation-prone materials (e.g., metal-organic frameworks, lithium battery cathode precursors)
• Gel electrophoresis drying and blot transfer under controlled low-pressure conditions
• Short-path distillation and Kugelrohr purification of thermally unstable natural products
• Evacuation of glove boxes and desiccators containing reactive atmospheres (e.g., SO₂, Cl₂, NH₃)
• Replacement of water-jet pumps in green chemistry labs seeking ISO 14001-compliant solvent recovery infrastructure

FAQ

Is the N840.3FT.18 suitable for vacuum filtration with aqueous HCl solutions?

Yes—its fully fluoropolymer-wetted path resists hydrochloric acid vapors up to 37% concentration at ambient temperature, provided condensate is trapped upstream.
Can it be operated horizontally or inverted?

No—this pump must be installed in the upright orientation specified in the KNF mounting manual to ensure proper diaphragm flexure and valve seating integrity.
What is the expected service life under continuous operation?

Based on accelerated life testing per DIN EN 14751, the diaphragm assembly maintains >95% flow retention after 15,000 hours of continuous runtime at 20°C ambient.
Does it require an exhaust condenser for acetone or dichloromethane use?

Yes—volatile organic solvents should be condensed prior to inlet to prevent diaphragm swelling and premature fatigue; KNF recommends inline cold traps or membrane-based solvent recovery units.
Is CE marking valid for use in the United States?

CE marking confirms compliance with EU directives; for U.S. deployment, verify local electrical codes (NEC Article 500/505) and consider UL recognition—KNF offers UL-listed variants (e.g., N840.3FT.18-UL) upon request.