KNF N820.3FT.18 Chemically Resistant PTFE-Lined Diaphragm Vacuum Pump

Overview

The KNF N820.3FT.18 is an oil-free, chemically resistant diaphragm vacuum pump engineered for demanding laboratory environments where exposure to aggressive vapors—such as concentrated hydrochloric acid, nitric acid, sodium hydroxide aerosols, or organic solvents—is routine. Unlike conventional vacuum pumps with elastomeric or aluminum wetted parts, this model features a fully PTFE-lined fluid path: the pump head is PTFE-coated, the diaphragm is solid PTFE, and all critical sealing components—including inlet/outlet valves—are fabricated from FFPM (perfluoroelastomer), a high-performance fluoropolymer elastomer with exceptional resistance to swelling, degradation, and permeation under corrosive conditions. Its dual-head configuration enables stable operation at ultimate vacuum levels down to 8 mbar while sustaining a continuous free-air flow rate of 20 L/min—making it suitable for integration with rotary evaporators, vacuum ovens, freeze dryers, gel dryers, and pressure-controlled distillation systems. Designed for unattended 24/7 operation, the N820.3FT.18 incorporates thermally optimized motor windings, low-friction PTFE bearings, and passive convection cooling—eliminating reliance on thermal cutouts or duty-cycle limitations common in lower-grade diaphragm pumps.

Key Features

• Chemically inert wetted materials: PTFE-coated pump head, solid PTFE diaphragm, and FFPM valve assemblies ensure long-term integrity when handling halogenated solvents, strong acids, bases, and oxidizing agents.
• Oil-free, maintenance-free operation: No lubricants required; no risk of oil backstreaming or contamination of sensitive vacuum lines or samples.
• Dual-head architecture: Enhances volumetric efficiency and extends service life by distributing mechanical load across two synchronized pumping chambers.
• Low noise and minimal vibration: Acoustic emission <52 dB(A) at 1 m; vibration amplitude <0.5 µm RMS—critical for vibration-sensitive instrumentation such as analytical balances or optical tables.
• Robust industrial-grade motor: 120 W brushless DC motor with integrated thermal monitoring and overcurrent protection, rated for continuous duty per IEC 60034-1.
• Compact footprint and ergonomic design: Dimensions of 154 × 207 × 312 mm (W × D × H); weight of 6.9 kg facilitates benchtop integration without structural reinforcement.

Sample Compatibility & Compliance

The N820.3FT.18 is validated for use with volatile and reactive sample classes including but not limited to: aqueous acidic/basic solutions (pH 0–14), chlorinated hydrocarbons (e.g., CH₂Cl₂, CCl₄), sulfur-containing compounds (e.g., SO₂, H₂S), and nitrogen oxides (NOₓ). It complies with EN 61000-6-3 (EMC emissions), EN 61000-6-2 (EMC immunity), and carries CE marking under the EU Machinery Directive 2006/42/EC. All materials meet USP Class VI biological safety requirements and are compatible with GLP and GMP workflows requiring documented material traceability. The pump’s construction supports audit-ready documentation per FDA 21 CFR Part 11 when paired with KNF’s optional digital interface module (N820.DIGI), which logs runtime, temperature, and fault events with timestamped, non-erasable records.

Software & Data Management

While the N820.3FT.18 operates as a standalone analog device, it is fully compatible with KNF’s N8xx.DIGI digital control module—a plug-and-play add-on enabling RS-485 Modbus RTU communication, real-time vacuum level feedback (via external Pirani sensor), programmable start/stop sequences, and event-triggered logging. Data export is supported in CSV format for integration into LIMS or ELN platforms. Firmware updates are performed via USB-C interface using KNF’s certified configuration utility, which enforces cryptographic signature verification to maintain system integrity in regulated environments.

Applications

• Rotary evaporation of acid-labile or base-sensitive compounds under reduced pressure
• Vacuum drying of catalysts, metal-organic frameworks (MOFs), or hygroscopic pharmaceutical intermediates
• Reduced-pressure distillation of corrosive solvent mixtures (e.g., HF/HNO₃ etchants)
• Gel electrophoresis chamber evacuation and blotting manifold operation
• Gas sampling and pre-concentration systems in environmental air monitoring labs
• Replacement for water aspirators in teaching labs seeking zero wastewater generation and consistent vacuum profiles

FAQ

Is the N820.3FT.18 compatible with vacuum controllers or automated lab systems?
Yes—when equipped with the optional N820.DIGI digital interface, it supports Modbus RTU protocol for bidirectional communication with PLCs, SCADA systems, or custom LabVIEW-based automation.
Can it be used with a cold trap for solvent recovery?
Yes—the pump’s chemical resistance allows safe integration with dry ice/acetone or liquid nitrogen cold traps; however, condensate collection must occur upstream of the pump inlet to prevent liquid ingress.
What is the expected service life under continuous operation?
Based on accelerated life testing per ISO 5211, the PTFE diaphragm and FFPM valves demonstrate >15,000 hours MTBF at rated load, assuming ambient temperature ≤35°C and relative humidity <80% non-condensing.
Does it require periodic calibration?
No—vacuum performance is inherently stable due to fixed-displacement mechanics; however, users may validate ultimate vacuum with a traceable Pirani or capacitance manometer annually as part of equipment qualification (IQ/OQ).
Is replacement part traceability available for regulated applications?
Yes—each PTFE diaphragm (part #N820.DIA.PTFE) and FFPM valve set (part #N820.VAL.FFPM) carries a unique batch number and material certification compliant with ISO 10417 and ASTM D1418.