Cases OverviewDriving Precision in Cooling Lubrication Systems
The Dosimetrix® hybrid cooling lubrication system uses a KNF Smooth Flow diaphragm pump to provide reliable, precise mixing and dosing of lubricants in metalworking machines.
Modern metalworking machines drive smart manufacturing and play a central role in Industry 4.0. They rely on intelligent cooling lubrication systems for maximum efficiency and a precise and high-performance machining process. For optimal mixing and dosing of the cooling lubricant, the Dosimetrix® hybrid from BRISCO Systems uses a KNF diaphragm liquid pump which provides an accurate and gentle media flow with minimal pulsation at the required performance.
Cooling Lubricants Play a Key Role in High-Performance Metalworking
Metalworking machines are critically important to many different industries, including aerospace, medical, and automotive. Modern machine tools use automated, computer-controlled tools that perform complex metalworking tasks like milling, turning, drilling, and skiving. Many of these machine tools can quickly switch between the different process steps and produce parts with complex geometries and high dimensional accuracy.
These machines rely on cooling lubricants that lower friction, dissipate heat, and reduce wear during the machining process. This ensures machining quality, process reliability and efficiency, and extends the service life of the tools. Cooling lubricants for metalworking machines usually consist of three components: water, base oils such as mineral or synthetic oil, and additives like emulsifiers, corrosion inhibitors, and high-pressure or anti-mist additives that enhance the desired properties of the cooling lubricant. The composition of the cooling lubricant is tailored to the specific application. Cooling lubricant systems allow for monitoring, mixing, and dosing the optimal lubricant composition and concentration.
Cooling Lubrication System Offers High Precision and Accuracy
For applications that require medium to large quantities of cooling lubricants, BRISCO Systems developed the Dosimetrix® hybrid, an IoT-connected, automated cooling lubrication system designed for precise fluid and cooling management. It delivers a constant and accurate mixture to ensure machining quality, efficiency and cost control. The system independently calculates the required refill concentration, maintains a consistent fill level, and can automatically supply correctly dosed top-up volumes to up to 100 separate tanks.
The Dosimetrix® hybrid cooling lubrication system consists of six components:
- Inlet connections for water and cooling lubricant concentrate where both flows are regulated separately
- High-precision valves and flow meters ensure accurate dosing in the range of 0.1-15 % concentration (accuracy ± 0.1 %)
- Mixing chamber where water and concentrate are mixed under controlled conditions
- Sensors that monitor flow rates, pressure, temperature, concentration, fill level, and leaks
- Control and operating module with display, control interface, or optional control via web portal
- Safety functions such as automatic overfill protection, leak detection, and emergency stop
A critical challenge in cooling lubrication systems is the reliable mixing of oil-water emulsions. Emulsion stability is strongly influenced by droplet size: smaller and more uniform droplets result in a stable mixture that maintains its cooling and lubrication properties over extended periods of time. Poorly formed emulsions are more prone to phase separation, which can lead to odor formation, reduced machining performance, and the need for premature replacement of the cooling medium, resulting in increased downtime and operating costs.
Consistent emulsion quality therefore requires controlled, repeatable dosing of the lubricant concentrate under defined flow conditions. To ensure fully automatic, high-precision mixing and dosing, the Dosimetrix® hybrid must deliver cooling lubricant independently of the fluctuating water pressure in the supply line. Because the lubricant is injected into a pressurized water pipe via a nozzle, changes in water pressure directly influence the required pump performance and the accuracy of the mixture. Achieving consistent mixing therefore requires a highly precise pump that can maintain stable flow under varying pressure conditions. In addition, the pump must offer a high performance-to-size ratio, good suction capacity, low pulsation, and strong chemical resistance.
Engineering Trust: KNF Introduces New Pump Solution for Reliable System Performance
In 2019, BRISCO Systems approached KNF with a request for test pumps capable of delivering a flow rate of 3 l/min at 6 bar (rel.) pressure. KNF provided the FP 400 and NF 1.300 diaphragm liquid pumps for evaluation. Initially, BRISCO Systems opted for a competitor’s standard double diaphragm pump with EPDM diaphragms, but the solution proved problematic in the cooling lubricant system. Despite not being selected at first, KNF maintained a collaborative relationship with BRISCO Systems through other projects.
By November 2022, the KNF engineers revisited the Dosimetrix® hybrid challenges on-site. The competitor pump was underperforming and suffering diaphragm damage caused by cavitation. With updated process parameters, KNF analyzed the situation and proposed a Smooth Flow diaphragm pump as a replacement, a pump that had not yet been available during the initial evaluation in 2019. Delivered for testing in December 2022, the liquid pump passed all trials and was integrated into the Dosimetrix® hybrid, where it now operates reliably and efficiently.
KNF Smooth Flow Pump Prevents Cavitation and Boosts Performance
At the heart of the Dosimetrix® hybrid cooling lubrication system, the diaphragm liquid pump draws lubricant from a container 1-1.5 m below the pump and feeds it into a pressurized water pipe via a nozzle. To handle fluctuating water pressure in the supply line or changing demand for new coolant, the system calculates the delivery rate at which the pump must supply the cooling lubricant.
Using KNF’s unique Smooth Flow technology, five diaphragms connected in parallel, each operating with a phase shift, generate a high, smooth flow with excellent linearity and minimal pulsation, preventing cavitation and protecting the pump and system. With a maximum flow rate of 4.4 l/min and pressure of 6 bar (rel.), plus self-priming and dry-running capability, the liquid pump ensures gentle, reliable coolant transfer, system integrity, and protects sensitive components. Its diaphragm technology provides leak-tight operation and prevents cross-contamination from additives, meeting the accuracy and reliability demands of machine tool applications.
Find out more about
KNF’s Smooth Flow technology.
Customized Diaphragm Pump for Cooling Lubrication System Provides Chemical Compatibility
Like all KNF diaphragm pumps, the Smooth Flow pumps are based on a modular system which allows the customization of the pump head, materials, and the mechanical, electrical and hydraulic connections. For the Dosimetrix® hybrid, chemical resistance to corrosive or neutral liquids is of utmost importance. The customized liquid pump used in the system is designed with EPDM diaphragms coated with PTFE, the valves are made of FFKM, the seals of FKM, and the pump head of PP – all of which ensure chemical compatibility with the various transferred liquids, especially oil-containing media. To ensure a perfect fit and save space in the system, KNF rotated the pump head by 180°. It also uses a brushless DC motor which provides adjustable performance of the pump and supports the precise mixing and dosing requirements of the cooling lubricant system.
“The pump from KNF offers a high performance-to-size ratio and can be integrated into the specialized control system of our Dosimetrix® hybrid. It was very important for us that the pump offers a low maintenance operation and long lifetime, because this reduces downtime and costs for our customers”, concludes Jürgen Gosch. The diaphragm liquid pump delivers lubricants with a precise and reliable flow across a wide operating range supporting accurate dosing in the cooling lubricant system. KNF has extensive experience in the design of tailor-made pump solutions. The engineers work closely with each customer to ensure a perfect fit of the pump and provide technical support throughout the integration process. Customers like BRISCO Systems benefit from KNF’s local support and expertise across various industries and markets.
