Coolant troubleshooting involves identifying and resolving issues related to the coolant system in machinery. This process typically includes diagnosing problems such as leaks, overheating, or inadequate cooling performance. The goal is to ensure that the coolant system operates efficiently to prevent equipment damage and maintain optimal performance.
We have compiled a guide for troubleshooting the following scenarios that may arise. Select the ones that relate to your situation the most to see the possible solutions.
Corrosion
- Too Weak Concentration: Adjust and maintain concentration as recommended by coolant manufacturer.
- Poor Water Quality/Corrosive Ion Buildup from Water: Use better quality water such as deionized, reverse osmosis or softened water.
- High Temperature/Humidity: Reduce temperature and humidity and/or use a supplementary rust preventative.
- Contamination: Identify and eliminate contaminants that promote corrosion, such as heat treating salts.
- Corrosive Atmosphere: Identify and vent corrosive fumes out of problem area. Could be from heat treat or propane forklift truck exhaust.
- Part Handling/Storage: Use clean, plastic dividers to allow parts to dry and remain separate. For extended storage, use a supplementary rust preventative
Poor Tool Life
- Too Weak Concentration: Adjust and maintain concentration as recommended by coolant manufacturer.
- Water Quality: Hard water (greater than 200 ppm Total Hardness) can promote mix instability in metalworking fluids and lead to loss of tool or wheel life.
- Changes: Verify that no changes have been made to the coolant, tooling or material you are working with.
- Contamination: Identify and eliminate or minimize contaminants that promote loss of tool or wheel life, such as high levels of hydraulic or way oils, floor cleaners or other coolants.
Foam
- Too Strong Concentrate: Adjust and maintain concentration as recommended by coolant manufacturer.
- Type of Operation: Some operations, such as high-speed milling or surface grinding, can promote foam. Work with your coolant supplier to implement the product properly suited for your operation.
- Contamination: Look upstream from operation. What chemical or lubricant has been in contact with the part, and how does this impact foam?
- Water Quality: Soft water (less than 100 ppm Total Hardness) can promote foam in some metalworking coolants.
- Coolant Level Low: Keep the sump full in order to maximize fluid retention time in sump and allow the air to come out of the mix.
- Mechanical Problems: Check the fluid delivery, filtration system, and fluid return systems for mechanical problems and repair them. Kinks in the hoses or small pinholes may allow air to be pulled into the system.
Coolant Instability
- Water Quality: Hard water (greater than 200 ppm Total Hardness) can promote an unstable mixture. Technology exists to prevent this, particularly in synthetic products.
- Contamination: Identify and eliminate or minimize contaminants that promote coolant instability. These may include tramp oils, way lubricants or chemicals from a previous process.
- Concentration: Adjust and maintain concentration as recommended by coolant manufacturer
Tackiness/ Stickiness/ Gooeyness
- Quality of Water: Hard water (greater than 200 ppm Total Hardness) can create tackiness in certain coolants. Your coolant supplier can provide coolants with blended additives that naturally soften the water.
- Delivery: Some machining centers may have “blind” areas where coolant in not in continous contact. With heat and time the water will evaporate, leaving a film that will cause chips to cling. A daily flush of the area with coolant will reduce this problem.
- Contamination: Identify and eliminate or minimize contaminants that promote coolant instability. These may include tramp oils, way lubricants or chemicals from a previous process.
Poor Surface Finish
- Concentration: Adjust and maintain concentration as recommended by manufacturer.
- Coolant Instability: When coolants become unstable (see “Coolant Instability” below), the additives can be depleted and lead to more rapid tool wear. This is common for older soluble oil formulations. Newer synthetic formulations do not have this problem.
- Changes: Verify that no changes have been made to the coolant, tooling or material you are working with.
Rancidity
- Concentration: Adjust and maintain concentration as recommended by coolant manufacturer.
- Circulation: Keep it moving. Circulating the tank will assist with sump life.
- Tramp Oil: Tramp oil can promote microbial growth, especially in soluble oil formulations. Implement preventative maintenance practices to minimize tramp oil. This will improve coolant life and minimize waste.
- Contamination: If adding water manually, use clean buckets. Minimize tramp oil and use oil skimmers.
- Micro-Biological Activity: If concentration and other factors are not the cause, then the use of a tank-side biocide may be necessary. Advancements in coolant technology have minimized this. If your coolant requires this, contact the manufacturer. A machine cleaner may be necessary to eliminate bacteria or fungus.