Cutting fluid

What is cutting fluid?

The purpose of cutting fluid is to cool and lubricate the machining process. In addition, cutting fluid cleans the tool and machine, removes chips from the work area, and provides corrosion protection for workpieces. An effective cutting fluid enables higher cutting speeds, extends tool life, and improves the surface finish and dimensional accuracy of workpieces.

The role of cutting fluid in machining

Cutting fluid is an essential factor for the efficiency and quality of machining. It reduces friction on the cutting surface, helping to keep both the workpiece and the tool cool. This is especially important when machining difficult-to-cut materials, such as stainless steels or aluminum alloys, which could otherwise overheat and cause tool wear.

Using the right cutting fluid can also prevent tools from welding to the material being machined, which improves machining accuracy and surface finish. For example, machining cast iron, which releases a lot of small metal particles, requires efficient chip removal to keep the machine and tools clean and functional. When working with copper alloys, corrosion prevention is key, and the right cutting fluid can provide the necessary protection.

High-pressure cutting fluid and its benefits

In recent years, high-pressure cutting fluid has taken on an increasingly important role in machining. High-pressure fluid jets, which can reach pressures up to 150 bar, enable effective machining of challenging materials such as Inconel and super duplex steels.

High-pressure cutting fluid improves chip control, especially in turning and drilling applications. Internal fluid supply to drills and turning tools prevents chips from jamming in chip grooves and ensures consistent cutting. This reduces the contact time between the tool and workpiece, which lowers cutting forces and temperature, while improving surface finish and tool durability.

The effect of cutting fluid on cutting and machining speeds

The right cutting fluid can allow for higher cutting speeds, enhancing production efficiency. Cutting fluid reduces friction and heat, making it possible to use higher feeds and depths of cut without sacrificing tool life or workpiece quality. This is particularly important in serial production, where every production run has cost implications.

Additionally, the lubricating properties of cutting fluid can improve the sharpness of the cutting tool and prevent wear, which in turn enhances the dimensional accuracy and surface quality of machined parts. This is especially crucial when machining materials that would otherwise cause significant wear, such as aluminum and titanium.

Selection and use of cutting fluid

Several factors need to be considered when choosing a cutting fluid: the materials being machined, the machining methods, and the characteristics of the machine's coolant system. The easiest materials to machine are cast iron and copper alloys, while highly alloyed steels and aluminum require more lubrication.

The right cutting fluid should provide not only cooling and lubrication, but also efficient chip removal and corrosion protection. Environmental and health factors, such as VOC emissions and skin irritation risk, also impact the choice of cutting fluid. Optimizing these factors ensures that machining is both efficient and safe.

Principles of high-pressure cutting fluid and pump features

Using a high-pressure fluid supply system improves chip breaking and prevents chips from sticking to tools. The cutting fluid pump system must provide sufficient pressure and flow cost-effectively. For example, in turning and drilling, fluid channels direct the jet precisely, allowing efficient machining and reducing downtime.

An effective cutting fluid system uses pumps that can maintain high pressure and consistent flow rate. The diameter and number of cutting fluid nozzles must be optimized to ensure efficient chip removal and cooling. This reduces tool wear and extends tool life, which is essential for high-quality and productive machining.

Cutting fluid maintenance

Although the focus is often on the machining aspect, it’s important to mention that regular maintenance and monitoring of cutting fluid are essential to optimize the process. Impurities and oils accumulating on the fluid surface must be removed, and the fluid’s concentration and pH should be checked regularly. The fluid system should also be cleaned periodically, which allows for continuous and effective operation while reducing bacterial growth and corrosion issues.

Summary

The significance of cutting fluid in machining quality and efficiency is undeniable. Its multiple roles in cooling, lubrication, cleaning, and corrosion protection ensure that the machining process runs smoothly, enabling higher cutting speeds and better surface quality. Implementing a high-pressure cutting fluid system and carefully selecting the appropriate fluid significantly enhance machining performance, while reducing tool wear and overall production costs. Careful selection and maintenance of cutting fluid, combined with effective machining techniques, are key to optimal and long-term production.