One concern is the level of chips, fines or swarf in the sump. Quantities of these small particles can provide an enormous surface area for bacteria to attach themselves, while at the same time creating “dead areas” where coolant cannot circulate. The easiest means to control solids is to clean out the sump on a regular basis and use some type of filtration.

Proper Mixing
Use a proportioning device to ensure proper mixing of coolant with water. Accurately and thorough mixing of the coolant with water is imperative. As a rule of thumb, run makeup concentration 60% as strong as initial charge, to compensate for evaporative losses. Never add coolant concentrate directly into the coolant sump.

Record Keeping
For each sump or system, maintain a record of coolant and water additions, as well as any testing results. This will ensure that product is being properly maintained and will help identify trends such as evaporation and makeup rates for the system.

When cleaning out machine reservoirs, remove conveyors and clean out swarf and chips that may be trapped beneath. Failure to perform this procedure will reduce the life of the new coolant charge.

Tramp Oil Removal
Ensure that Tramp Oils (hydraulic oil, way lubes or other process oils) are continually being removed from the surface of the coolant sump. These oils can provide food for bacteria, thereby reducing the life of the coolant. Fix oil leaks in the machine!

Use a refractometer to check coolant concentration on a daily basis. Before checking, ensure the refractometer is calibrated to zero (use the same water that is used to mix coolant). Maintain concentration at recommended levels.