A larger settling tank or re position coolant pump intake may offer more time for the fluid to settle swarf. A coolant with less surfactant may also allow faster swarf settling. Coolant supplier should have a faster settling coolant you should check. bruce

My suggestion is a pumpout of flulid and cleaning of the lines. Typicall you cna add a cleaner like simple green or other at a 10% rate tot he existing fluid, circulate then dump. Recharge only with a soluble oil type that can handle keeping the swarf in suspension through the return lines to the sump to ultimately be removed by filtration.

We experienced an issue that sounds similar in a centerless OD grinder. The metals varied, but there was swarf buildup on the wheel, troughs, sides of the machine, and some float in the sump. Only gravity filtration is used in this grinder. We thought this might be contributed to way lube. The grinder has a way lube leak and the way lube may be clumping the fine swarf and depositing the buildup in the machine. The coolant was formulated to reject tramp oils. We were using Durakut 5035 from Falcon Industrial, and we added a detergent package machine side, 50/50 RA 40 and B25-5. This seemed to give the coolant more cleaning effect and to emulsify some of the tramp oil.

What is the surface tension of your coolant? Are the fines ferro magnetic, if so use magnets? What is the residence time in the dirty tank, needs to be greater than 5 minutes for the foam to release and allow suspended solids to drop out? Do you use bag filters and cloth drags? Are you running on towns water or demin/softened? - insoluble soaps, check pH/ Ca 2+ & Mg 2+ levels, adjust total hardness of fluid to between 75 - 125ppm, this should alter the surface tension and help but all need to be with a virgin fill or you'll blind out all the filters and flood/shutdown the pumps with back pressure.