KNF N811KN(T).18 Compact Diaphragm Vacuum Pump

Overview

The KNF N811KN(T).18 is a compact, oil-free diaphragm vacuum pump engineered for reliable, maintenance-free operation in demanding laboratory environments. Based on KNF’s proven positive-displacement diaphragm technology, it generates vacuum via reciprocating PTFE-coated or EPDM elastomeric membranes driven by an eccentric cam mechanism—eliminating lubricants, hydrocarbon contamination, and vapor backstreaming. Designed for continuous duty at ambient temperatures (5–40 °C), the N811KN(T).18 delivers stable suction performance up to 11.5 L/min at atmospheric inlet pressure and achieves ultimate vacuum levels between 240 mbar (N811KN.18) and 290 mbar (N811KT.18), making it suitable for low-to-medium vacuum applications including filtration, degassing, solvent recovery, and vacuum drying. Its sealed, brushless DC motor ensures consistent speed control and long service life (>10,000 h MTBF), while integrated thermal protection prevents coil overheating during extended operation.

Key Features

• Oil-free operation ensures zero risk of sample contamination—critical for analytical chemistry, pharmaceutical QC, and cell culture workflows.
• Chemically resistant fluid path: PPS polymer housing, PTFE-coated or EPDM membranes, and FFPM/FPM valve materials provide compatibility with common organic solvents (e.g., acetone, ethanol, ethyl acetate), weak acids (e.g., dilute HCl, acetic acid), and alkaline vapors (e.g., ammonia, sodium hydroxide solutions).
• Low noise emission (<52 dB(A)) and minimal mechanical vibration enable integration into shared lab benches and laminar flow hoods without disturbing sensitive instrumentation.
• Compact footprint (187 × 157 × 90 mm) and lightweight design (2.5 kg) facilitate benchtop deployment, mobile cart mounting, or integration into OEM analytical systems.
• No external cooling required; passive convection heat dissipation eliminates need for water lines or forced-air fans—fully replacing traditional water aspirators and rotary vane pumps in non-high-vacuum applications.
• UL-recognized motor and CE-compliant construction meet international electrical safety standards (EN 61000-6-3, EN 61000-6-4) and support use in ISO 17025-accredited laboratories.

Sample Compatibility & Compliance

The N811KN(T).18 is validated for handling non-explosive, non-particulate, and non-condensable gas streams typical in academic and industrial labs. It is not rated for use with halogenated solvents (e.g., chloroform, DCM), strong oxidizers (e.g., nitric acid fumes), or high-boiling-point condensables (e.g., glycerol, silicone oils) without optional cold trap integration. All wetted materials comply with USP Class VI and FDA 21 CFR §177.2430 for indirect food contact, supporting GLP/GMP-aligned processes. Device documentation includes full material declarations (RoHS, REACH SVHC), traceable calibration certificates (optional), and conformity statements aligned with EU Machinery Directive 2006/42/EC.

Software & Data Management

While the N811KN(T).18 operates as a standalone analog device, its motor controller supports 0–10 VDC or 4–20 mA analog input for external speed modulation—enabling integration into LabVIEW, DeltaV, or Siemens PCS7-controlled vacuum manifolds. Optional digital interface modules (e.g., KNF’s SmartLink adapter) provide Modbus RTU output for real-time monitoring of runtime hours, temperature, and fault codes—supporting predictive maintenance logs and 21 CFR Part 11–compliant audit trails when paired with validated SCADA platforms. Firmware updates are performed via USB-C using KNF’s certified configuration tool (v3.2+), with version history retained in internal non-volatile memory.

Applications

• Vacuum-assisted gravity filtration of aqueous and organic suspensions (e.g., Buchner funnel setups, membrane filtration of cell lysates).
• Solvent removal under reduced pressure during rotary evaporation pre-concentration or parallel synthesis workups.
• Inert atmosphere purging and degassing of solvents prior to air-sensitive reactions (e.g., Grignard, organolithium preparations).
• Supporting vacuum ovens and desiccators used in moisture content analysis (ASTM D1557, ISO 1183-1).
• OEM integration into automated liquid handlers, environmental samplers, and portable GC sample introduction modules.

FAQ

Can the N811KN(T).18 be used for vacuum distillation?
No—it lacks the ultimate vacuum depth (<50 mbar) required for efficient fractional or short-path distillation. It is optimized for rough vacuum tasks only.
Is PTFE membrane standard or optional on the N811KT.18?
PTFE-coated membrane is standard on the KT variant; the KN variant uses EPDM. Both are interchangeable via factory service kit (P/N: MEMB-N811-PTFE or MEMB-N811-EPDM).
Does this pump require periodic maintenance?
No scheduled maintenance is needed. Membrane and valve replacement is recommended only after 10,000 operating hours or if performance degradation (e.g., >15% flow loss at rated conditions) is observed.
Can multiple N811 units be manifolded to increase total flow?
Yes—parallel connection is permissible if inlet lines are individually filtered and equalized; however, ultimate vacuum remains unchanged, and total flow scales sublinearly due to system impedance.
What certifications does the N811KN(T).18 hold for use in regulated pharmaceutical labs?
It carries CE marking per EMC and LVD directives, RoHS compliance, and UL recognition (E339722) for component-level safety. Full 21 CFR Part 11 validation requires site-specific IQ/OQ protocols executed by qualified personnel.