KNF FP 70 Low-Pulsation Diaphragm Liquid Pump

Overview

The KNF FP 70 is a compact, high-integrity low-pulsation diaphragm liquid pump engineered for precise, contamination-free fluid handling in demanding laboratory and analytical instrumentation environments. Based on KNF’s proprietary linear-motion diaphragm actuation principle, the FP 70 delivers smooth, pulse-minimized flow without the need for dampeners or external pulsation suppression hardware. Its dry-running, oil-free architecture eliminates risk of lubricant carryover—critical for applications involving ultra-pure, reactive, or biologically sensitive media. Designed and manufactured in Switzerland, the FP 70 operates across a wide pressure differential range (up to 2 bar relative), with a maximum volumetric flow rate of 0.7 L/min and self-priming capability up to 3 mWg suction lift. Its lightweight construction (260 g) and low power consumption (8.3 W) make it ideal for integration into space-constrained, energy-sensitive platforms including portable analyzers, OEM medical devices, and inline process monitoring systems.

Key Features

• Low-pulsation fluid delivery enabled by precision-machined linear diaphragm motion and optimized valve dynamics
• Fully oil-free, maintenance-free operation with no lubricants contacting the fluid path
• Self-priming capability up to 3 mWg—enables reliable startup without pre-filling or external priming assistance
• Digitally adjustable motor speed (via analog voltage or PWM input) for fine-grained flow control and system-level synchronization
• Chemically resistant wetted materials: PP pump head, EPDM or PTFE diaphragms, EPDM or FFKM valves—validated for compatibility with aggressive solvents, acids, bases, and biofluids
• NSF certification confirms suitability for food-contact and potable water applications per NSF/ANSI Standard 51
• Brushless DC and standard DC motor variants available—supporting both continuous-duty and intermittent operation profiles
• Robust electromagnetic design ensures high reproducibility over >10,000 hours MTBF under typical lab conditions

Sample Compatibility & Compliance

The FP 70 is compatible with neutral, mildly corrosive, and highly aggressive liquids—including aqueous solutions, organic solvents (e.g., methanol, acetone), dilute mineral acids (HCl, HNO₃), alkaline reagents, and sterilants (e.g., hydrogen peroxide, peracetic acid). Its material configuration supports long-term exposure at ambient temperatures (5–40 °C) and pressures within its rated envelope. The pump meets key regulatory and quality frameworks: it is NSF-certified for food equipment (NSF/ANSI 51), complies with RoHS and REACH directives, and is constructed to support GLP-compliant workflows when integrated into validated instrument platforms. While not intrinsically rated for explosive atmospheres, its low-energy motor and non-sparking design facilitate safe use in Class I, Division 2 environments when properly installed.

Software & Data Management

As an OEM component, the FP 70 does not include embedded firmware or onboard data logging. However, its analog/PWM speed interface enables seamless integration with host system controllers (PLCs, microcontrollers, DAQ modules) for closed-loop flow regulation and real-time status monitoring (e.g., stall detection via current draw analysis). When deployed in FDA-regulated instruments (e.g., IVD analyzers), the pump’s deterministic behavior, traceable manufacturing origin (Switzerland), and documented material certifications support 21 CFR Part 11 compliance through appropriate system-level audit trail implementation. KNF provides full material declarations (IMDS), RoHS/REACH documentation, and test reports upon request for IQ/OQ validation protocols.

Applications

• Analytical instrumentation: Reagent delivery in HPLC sample loops, ICP-MS peristaltic bypass lines, and spectrophotometer fluidics
• Medical diagnostics: Metered dosing in point-of-care immunoassay platforms and hematology analyzers
• Environmental monitoring: Continuous sampling in stack gas scrubbers and wastewater nutrient analyzers
• Semiconductor fab tools: Precise chemical dispensing in wafer cleaning and etch verification systems
• Food & beverage QC: Sanitary transfer of calibration standards and flavor emulsions in inline NIR analyzers
• Fuel cell R&D: Humidification loop control and electrolyte circulation in PEM stack test benches
• Inkjet printhead priming and maintenance fluid management in industrial printing systems

FAQ

Is the FP 70 suitable for sterile or USP compounding applications?
Yes—when configured with PTFE diaphragms and FFKM valves, and operated within validated parameters, the FP 70 supports ISO Class 5–7 cleanroom integration; however, end-user sterilization validation (e.g., autoclave, gamma) must be performed independently.
Can the FP 70 run dry continuously?
Yes—it is explicitly designed for indefinite dry-run operation without mechanical damage or performance degradation.
What is the recommended service life under continuous 24/7 operation?
At nominal load (≤70% max flow/pressure), mean time between failures exceeds 10,000 hours; lifetime is primarily influenced by chemical compatibility and thermal management in the host system.
Does KNF offer custom wetted material sets or electrical interfaces?
Yes—custom diaphragm, valve, and seal material combinations, as well as tailored cable assemblies, connector types (e.g., M8, JST), and control signal conditioning are available under NDA-supported OEM development programs.