Water-Based Cutting Fluid Foam Response
The water based cutting fluid is a cutting fluid that is widely used in many metal cutting processes. This fluid contains water, oil, detergents and other proprietary components. The water carries enough oil components to create a stable interface. This interface has many benefits in cutting, such as cooling, lubrication, boundary film strength and chip flow. Among them, the cooling effect is the most significant.
A typical cutting system contains a pump, coolant system, cutting table or bed, nozzles and the actual cutting tools. Without the lubrication effect of the cutting fluid, the tool will become much hot, the workpiece too. The heat generated from cutting can cause hardening of the material, thus reducing the cutting ability of the tools. The heat generated by cutting can also cause deformation of the workpiece, which increases the cost of machining and increases the difficulty of machining.
When used in the correct way, the cutting fluid should keep the temperature of the cutting zone consistent. However, in some situations, excessive foaming can occur in the cutting fluid. Foaming affects the cooling efficiency of the cutting fluid, reduce the concentration of lubricant, increase the possibility of dryness. This can create a risk of annealing the workpiece, increasing tool wear and even breakouts.
The foaming of cutting fluid can be caused by a variety of factors. Some common causes are too much agitation, excessive dwell time in cutting operations, inadequate coolant system design, non-ideal cutting conditions, air entrainment, inadequate system filtration or contamination.
The key to managing foam is to identify any potential sources of foam and to take steps to eliminate them. The maintenance and filtration of cutting fluid is critical to avoid excessive foam. The filtration system must be correctly sized to remove dirt and particles, and the coolant must be checked for the correct concentration of active ingredients and the cleanliness. Adding the correct surfactant can reduce foam and the stability of some metalworking fluids can also help. In some cases, it may be necessary to reduce the cutting speed or add more cutting fluid.
In addition, the concentration of the metalworking fluid should usually be low, usually between 10 and 15 percent. For applications with higher foam generation potential, this concentration should be further reduced. In some cases, it could be beneficial to add anti-foaming agents to reduce foam, but this should always be carefully and specifically considered on a case-by-case basis and the suitability of the fluid tested.
To ensure the right amount of foam is maintained and that further foaming is prevented, it is important to consider the cutting process and the coolant system. If possible, optimise the cutting parameters, use surfactants to reduce foam levels and modify coolant system components. This could include replacing nozzles, changing the location of filters and other related components, changing the coolant system layout or adjusting the cutting speed.
Although foam in water based cutting fluids is not ideal, it can be managed and reduced with the right steps in place. By understanding the potential sources of foam, taking steps to minimise it and constantly monitoring the system, it is possible to ensure the right balance is maintained for efficient and effective cutting operations.
