KNF equipment

About KNF

KNF is a German manufacturer of diaphragm vacuum pumps and diaphragm liquid pumps for laboratory, OEM, and process applications. Kurt Neuberger founded the company in 1946 in Freiburg im Breisgau, Germany, initially focusing on engine repair and thread-cutting machinery before pivoting to diaphragm pump development in 1962. It is headquartered in Freiburg-Munzingen and remains an independent, family-owned business under the Becker family, with no external parent company. The product range covers diaphragm vacuum pumps, liquid transfer pumps, dosing and metering pumps, complete vacuum pump systems, and OEM gas and liquid pump components. Its best-known lines are LABOPORT, SIMDOS, and LIQUIPORT. On Questpair, these pumps are listed in both new and used condition by verified suppliers and distributors.

The defining feature across the range is the diaphragm principle itself: a flexible membrane moves gas or liquid without the fluid touching any oil or lubricant. That oil-free, hermetic design is why these pumps are common in chemistry and life sciences, where a contaminated vacuum line or transfer path can ruin a sample.

KNF pump lines on Questpair

LABOPORT is the vacuum family, diaphragm vacuum pumps built for filtration, degassing, aspiration, and drying. In life sciences these pumps drive vacuum filtration of buffers and culture media, the kind of sterile filtration step that precedes cell culture work, and they pull vacuum for solid phase extraction manifolds. They also evacuate rotary evaporators during solvent removal. A diaphragm vacuum pump for rotary evaporation is a frequent search because the oil-free chamber tolerates solvent vapour that would degrade an oil pump.

SIMDOS covers dosing and metering. These are diaphragm liquid dosing pumps that deliver a set volume with each stroke, used for reagent addition, buffer preparation, and the controlled liquid handling that sits behind reproducible assay work. A metering pump for reagent dispensing is specified where volume accuracy matters more than throughput.

LIQUIPORT handles liquid transfer, moving fluids in bulk rather than metering them. A portable diaphragm liquid transfer pump of this kind is used for emptying containers, recirculating process liquids, and sampling, including in bioprocessing where a pump must move media or product without shear damage or contamination. Alongside these three lines, KNF supplies complete vacuum pump systems and OEM components that are built into third-party instruments, which is why a KNF pump head often sits inside an analyser without the brand showing on the outside.

How KNF pumps are listed and priced?

The catalogue holds both new and used stock. Of the KNF listings, 48 percent are used. Used units are listed below new ones, which is the price difference a buyer can count on; warranty and any support terms are set per listing and arranged in consultation rather than fixed across the brand.

Prices range from EUR 40 to EUR 9.024. The average sits near EUR 1.857. The low end is where small benchtop vacuum pumps and individual pump heads appear, and the high end is where complete systems and larger process pumps sit, so the price field is the fastest way to tell a simple filtration pump from a full system.

Supply comes from 14 verified suppliers and distributors across 7 countries, which gives a buyer several listings to weigh on model, condition, and price before deciding. Parts for KNF pumps can be sourced via Questpair, and manuals or documentation can be requested through Questpair, where specialists respond within the hour. What the listing data does not describe is a refurbishment standard: the catalogue separates new from used and no further, so a buyer who needs a documented service history should check the specific listing.

Questpair review of KNF

Our take based on listings data and supplier feedback

KNF occupies a specific niche: diaphragm pump technology applied to vacuum generation, liquid transfer, and precise dosing. For a lab buyer, the first thing worth knowing is that the listings on Questpair are not a single pump type but a cross-section of the KNF range, and that breadth is what makes the catalogue useful for comparison.

The vacuum side is anchored by the LABOPORT line, diaphragm vacuum pumps used for filtration, degassing, rotary evaporation, and solvent handling. The oil-free diaphragm principle is the reason these units appear so often in chemistry and life sciences settings: there is no oil mist to contaminate a sample stream, which matters for vacuum filtration and for evacuating a rotary evaporator. On the liquid side, SIMDOS covers dosing and metering, and LIQUIPORT handles liquid transfer. A buyer weighing a dosing pump against a transfer pump is really choosing between controlled volume delivery and bulk movement, and having both families listed under one brand lets that comparison happen without jumping between manufacturers.

Condition is the second practical axis. The KNF listings split close to evenly, with 48 percent used, so a buyer who wants a new unit and one who wants to save on a second-hand pump both have stock to work from. Used and new units are listed at different price points, and the used pumps sit below new. That is the one difference a buyer can rely on from the listing data alone; everything else, including warranty, is set per listing rather than centrally, and warranty is arranged in consultation for the specific unit.

Price range is wide, from EUR 40 to EUR 9.024, with an average around EUR 1.857. That spread reflects what the catalogue holds: small benchtop vacuum pumps at the low end and larger pump systems at the high end. A buyer scanning for a basic filtration pump and a buyer specifying a process-scale system are looking at the same brand but very different line items, and the price field is the quickest way to separate them.

Supply depth is the third point. KNF pumps come from 14 verified suppliers and distributors spread across 7 countries. For a procurement manager that matters because it widens the set of listings to compare on condition, price, and model before committing. Parts for KNF pumps can be sourced via Questpair, and documentation requests go through Questpair as well, with specialists responding within the hour. What the data does not support is any claim about refurbishment grade: the catalogue distinguishes new from used and nothing finer, so a buyer wanting a specific service history should read the individual listing rather than assume a standard.

**Vacuum and transfer pumps in one catalogue**

KNF builds diaphragm vacuum pumps, liquid transfer pumps, and dosing pumps, and the Questpair listings cover all three families rather than a single pump type.

**Both new and used condition on offer**

Of the KNF listings, 48 percent are used, giving buyers a choice between new units and lower-priced second-hand pumps within the same brand.

**Supply spread across several European countries**

KNF pumps are offered by 14 verified suppliers and distributors across 7 countries, which widens the pool a buyer can compare against.