Mahr Metering Systems, part of the family owned Mahr Group in Göttingen, makes Feinpruef gear metering pumps used for distillation feed, filling and dosing.
Mahr Metering Systems GmbH is the gear pump business of the Mahr Group, a family owned technology company founded in 1861 in Esslingen by Carl Mahr and headquartered in Göttingen, Germany. Its precision gear metering pumps grew out of the Feinprüf works in Göttingen, which is why cannabis operators often see them listed as Mahr Feinpruef pumps; the US company, Mahr Metering Systems Corp., produces in Charlotte, North Carolina.
Mahr pumps meter liquids for fiber spinning, adhesives, coatings, chemicals, plastics, packaging and medical technology. In cannabis, one common place to find one is the feed system of a short path still, where a small displacement gear pump sets how fast crude enters the evaporator. Urth & Fyre lists used Mahr pumps when they come off production equipment and sources new units on request.
Mahr's company brochure lists these displacement ranges in cc per revolution:
For chemical duty, the Mahr chemical gear pump page lists viscosities from 1 to 1,000,000 mPas, temperatures up to 300 °C and 120 bar standard pressure, with stuffing box, rotary, single or double mechanical seals or magnetic coupling. Electrical, liquid or steam heating is available, and an ATEX version of the pump and drive is offered.
Chemtech Services says its MINI-4, MINI-5, KDL-6 and KDT-6 short path units use high precision gear pumps for automatic feed control, and its lab units share a gear pump feed metering system. The 0.3 cc/rev Mahr Feinpruef pump Urth & Fyre lists is described as compatible with the KD-6 heatable top plate used on those models. When a feed pump wears, feed rate drifts and the cut points move with it.
Gear pumps deliver a fixed volume per revolution with low pulsation, so a servo or stepper drive can dose by counting turns. That suits cartridge and vial filling of heated oils, where viscosity changes with temperature. Our post on cartridge fill quality, needle gauge and viscosity windows covers the process side.
Meter mix dispense systems and larger MarChem pumps fit blending lines where two or more liquids are proportioned continuously.
Chemtech describes manual feed as an operator setting rate with a precision valve, relying on visual cues and experience, while automatic feed uses a gear pump to regulate rate and can run programmed profiles through a PLC. Mahr describes its pumps as delivering precise rates with minimal pulsation, meaning uniform, continuous pumping without pressure swings. That repeatability is the reason to pay for a gear pump over a needle valve on a production still.
Read the Mahr metering history for the Feinprüf background, and see the Distillation Equipment Guide for how feed control fits into the full distillation train.
Urth & Fyre lists a used Mahr Feinpruef metering gear pump with 0.3 cc/rev displacement, built in 2018 and located in Nevada, described as compatible with the KD-6 heatable top plate on Mini-4, Mini-5, KDL-6 and KDT-6 stills. For new pumps, we source and quote Mahr units against your fluid, flow and temperature.
Review the Mahr 0.3 cc/rev metering gear pump listing for condition and pricing, or request a quote with your fluid, flow rate and operating temperature.
Who makes Feinpruef gear pumps?
Mahr makes Feinpruef gear pumps. The Feinprüf works in Göttingen built its first prototype gear pumps around 1948, and the spinning pump division became Mahr Metering Systems GmbH in 2001. Mahr Group is a family owned company founded in 1861 and headquartered in Göttingen, and its US arm, Mahr Metering Systems Corp., produces in Charlotte, North Carolina.
What is a gear metering pump used for in cannabis?
A gear metering pump moves a fixed volume per revolution, so it sets feed rate precisely. In cannabis it most often feeds crude into a short path or wiped film still, where Chemtech uses gear pumps for automatic feed on its KD series lab units. Gear pumps are also used to dose heated oils in filling and to proportion liquids in blending.
How do I calculate flow from a gear pump's cc/rev rating?
Multiply displacement by speed. A 0.3 cc/rev pump turning at 60 rpm delivers 18 cc per minute, which is about 1.1 liters per hour. Pick a displacement that puts your target flow in the middle of the drive's speed range, then confirm by timing a measured volume after installation.
Is the Mahr pump compatible with a Chemtech KD-6 still?
The 0.3 cc/rev Mahr Feinpruef pump Urth & Fyre lists is described as compatible with the KD-6 heatable top plate used on Mini-4, Mini-5, KDL-6 and KDT-6 units. Confirm the mounting pattern, shaft coupling and drive on your still before ordering, and check that the pump's temperature rating matches your feed temperature.
Are Mahr pumps rated for hazardous locations?
Mahr offers an ATEX version for both the pump and the drive on its chemical gear pumps, but it is an option rather than standard. If the pump will sit in a classified extraction or distillation room, specify the rated version and a matching drive, and confirm the requirement with your engineer and fire marshal.
Can I buy a used Mahr metering pump?
Yes. Urth & Fyre lists a used Mahr Feinpruef metering gear pump with 0.3 cc/rev displacement, built in 2018 and located in Nevada. Check shaft drag, seal condition and displacement on the nameplate before installing it, and calibrate by timing a measured volume. Urth & Fyre also sources and quotes new Mahr pumps.