Overview
Chips, machining fluids, and other debris created while machining metals and other materials cause problems in machining operations. Clogged and corroded fluid passageways create erratic fluid spraying and improper lubrication, leading to increased carbide wear, poor surface finishes, poor chip flow and poor cutting rates. Overheating of the cutting tools, which can cause excessive tool wear and reduced service life, can also be a common problem caused by the debris. To minimize these problems, fluid filtration and continuous flushing of the machine and coolant tank should be used.
Filtration
Regular and accurate filtration of machining fluids should be used to prevent valuable coolants from becoming dirty and damaging the cutting process and also to reduce the production of chips, swarf and dust. The finest filtration system suited for the application should be used. As filters become dirty, fouling will occur resulting in increased pressure drops and eventually filter bypassing, which can cause clogged and corroded fluid passageways, leading to erratic spray, poor surface finishes, poor chip flow and poor cutting rates.
Continuous Flushing
Continuous flushing is a process that actively cleans the machine’s coolant tank and coolant supply line by utilizing a continuous stream of fresh coolant, which then flushes the chips and other debris from the tank. This process helps to reduce the accumulation of debris in the tank and supply lines, increasing tool life, reducing carbide wear and increasing the life of the machining fluid.
Coolant Additions
Regular coolant additions prolong the life of water soluble or chemical based machining fluids and help to compensate for periodic maintenance (such as draining and filter changes) that can disrupt a fluids chemistry. Adding the correct amount of concentrated coolant can extend the coolants life and effectiveness.
Maintenance
Maintenance of the coolant tank, filters, and other equipment should be performed regularly in order to maximize the life of the machining fluid. The coolant tank should be drained and filters should be changed as needed in order to remove any of the debris that has accumulated. All hoses should be checked for any signs of wear and should be replaced as necessary.
Chemical Phosphate Treatments
Chemical phosphate treatments should be used to protect against bacteria and fungus growth, rust and corrosion of tank walls, and other contaminants. The phosphate treatment will also help to improve surface finish and part cleanliness and reduce bad odors.
Conclusion
Using proper filtration, flushing, coolant additions, and maintenance of coolant tanks and filters are essential to ensure efficient and cost-effective machining operations with optimum part quality. Using these methods increases tool life, chip removal, and overall cost savings from reduced downtime and tool replacement.
