Oil-based cutting fluids vs Water-based cutting fluids
The cutting of materials, either by grinding or turning, is a common industrial process used in the production of many components. In order to ensure that the cutting surfaces are sufficiently lubricated and cooled in order to prevent damage to the surface of the component and the cutting machine, cutting fluids are used during the process. Two main types of cutting fluid are in use today, oil-based and water-based.
Oil-based cutting fluids are usually mineral-based and are the most commonly used form of cutting fluid. These fluids help in lubricating the component and the cutting tool, preventing tool wear and heat buildup, which can degrade the cutting surface and damage the cutting tool. As these fluids have lower vapor pressures they are less prone to evaporating during the cutting process, however they are also prone to becoming contaminated by dust and dirt, which can reduce their effectiveness.
Water-based cutting fluids are prevalent within machining centres, particularly in the form of synthetically produced foam and mist lubricants. These lubricants help to cool the component being machined as well as helping to reduce friction between the tool and the component. The addition of water in the form of mist increases the contact between the two surfaces and helps to reduce cutting forces and increase productivity. Furthermore, due to their lower cost of manufacture, water-based lubricants are generally cheaper than their oil-based alternatives.
However, there are also some downsides to the use of water-based cutting fluids. As the water can evaporate, air pockets can form between the cutting surfaces causing a loss of the cutting fluid, which could lead to cutting tool wear. Additionally, water is also an excellent conductor of heat, so much so that it can be detrimental to certain components, depending on the type of material being machined. This can result in a reduction in tool life, as well as a decrease in overall productivity.
Ultimately, the type of cutting fluid that is best suited to a particular application will depend upon the type of material being machined, the process and the cutting tool. For example, water-based lubricants should be used in applications involving non-ferrous materials such as aluminum, while oil-based lubricants are more suited to machining components from ferrous materials such as steel.
In conclusion, both oil-based and water-based cutting fluids play an important role in the machining process and the selection of the most appropriate lubricant for a particular application should be based upon a detailed understanding of the machining requirements. By understanding the characteristics and compatibility of the cutting fluid in comparison to the material and cutting tool, the selection of the correct fluid will be simplified, resulting in improved performance, increased productivity and better overall results.
