Problem Description Foaming in high-pressure coolant systems is a persistent issue in deep hole drilling. I have watched a perfectly good 80-bar coolant system turn into a frothy mess that could not clear chips from a 12 mm hole. The air bubbles compress under the high pressure and expand at the nozzle, reducing the effective cooling and lubrication at the cutting zone. When the coolant aerates, chip evacuation is the first thing to fail. ...
I use coolant additives to improve cutting performance and extend coolant life in deep hole drilling operations. The right additive makes a noticeable difference in tool life, surface finish, and coolant system reliability. Over the years I have tested various additive combinations and developed guidelines for what works in different applications. Types of Coolant Additives and Their Applications Coolant additives serve specific purposes and are not interchangeable. I use four main categories of additives, each with a specific function and application window. ...
Problem Description Foaming robs a high-pressure coolant system of its ability to evacuate chips. The air bubbles in foam take up volume that should be occupied by liquid coolant. I’ve watched a foaming system lose 35% of its chip-carrying capacity — the chips stopped flowing out of the bore and started packing. In deep hole drilling, where chip evacuation depends entirely on coolant flow, foaming is one of the most disruptive problems you can encounter. ...
I have spent a lot of years watching machinists blame the tool, the feed rate, or the material when the real culprit is sitting right in the coolant tank. Coolant for deep hole drilling is a chemical cocktail, and each additive serves a specific purpose. Understanding what each one does and how they interact is the difference between a process that runs all shift and one that burns through drills before lunch. Here is what I have learned, the hard way. ...