Low bacterial counts.
Over a year without extra biocide.
A mechanical-engineering company used FMF 310/3 magnetic filtration to remove fine particles from coolant used to machine cast components. After more than a year, black deposits had disappeared, and bacterial counts remained stable at a low level without extra biocide. The filter’s cleaning interval gradually increased to 48 hours.
Case background
Coolant flushes the chips out of the machines. Coarse chips settle in a collection tank and are removed by a scraper conveyor.
The challenge
Large quantities of small chips and particles were pumped with the coolant to a belt filter. Coarser chips settled on the filter belt and were removed, but the fine particles produced when machining cast iron—especially those below 50 µm—passed through.
These particles accumulated in the clean tank beneath the belt filter. After several months, black deposits covered the machine interior, and coolant analysis confirmed a high particle load despite the existing filtration.
During a coolant change, a layer of black sludge several centimetres deep was found on the tank floor. The sludge and high particle concentration promoted severe bacterial growth, making repeated additions of biocide necessary.
The solution: FRIESS FMF310/3 magnetic filtration
Results
As the system became cleaner, the maintenance interval increased first to 24 hours and later to 48 hours. Fine particles that had previously remained in circulation were now separated safely and reliably.
The machine interior became visibly cleaner and the black deposits disappeared. Even after more than one year, the bacterial count in the coolant remained stable at a low level without additional biocide.
Following this result, other machines at the company were also equipped with FMF 310/3 magnetic filters.
Fine particles and sludge building up alongside recurring microbial contamination in your coolant?
Please share your workpiece and particle materials, particle-size range, circulation flow rate, coolant volume, existing filtration rating, sludge build-up, microbial test results and maintenance schedule. Our China engineering team can assess the magnetic particle load and recommend an FMF magnetic filter configuration and installation position. Magnetic filtration supports particle and sludge control; it does not replace coolant monitoring or appropriate microbial management.