How to choose cutting fluid for seamless aluminum tube processing

Compared with most steel and cast iron materials, the seamless aluminum tube has many obvious characteristics in terms of physical properties: the strength and hardness are much higher than pure aluminum, but compared with steel, the strength and hardness are lower, the cutting force is small, and the heat conduction Good sex.
Due to the soft quality and high plasticity of the seamless aluminum tube, it is easy to stick to the knife during cutting, forming built-up edge on the cutting tool, and welding may occur on the cutting edge during high-speed cutting, which will cause the cutting ability of the cutting tool to be lost, and affect the machining accuracy and surface roughness. Spend. In addition, the thermal expansion coefficient of the seamless aluminum tube is large, and the cutting heat can easily cause thermal deformation of the workpiece and reduce the machining accuracy.
Selection of cutting fluid for seamless aluminum tube processing
To sum up, the selection of cutting fluid for seamless aluminum tube processing is very important, and good lubricity, cooling, filterability and rust resistance must be guaranteed. Therefore, cutting fluid for seamless aluminum tube processing has a certain It is very necessary to choose a suitable cutting fluid.
According to the different requirements of processing conditions and processing accuracy, different cutting fluids should be selected. Because high-speed machining can generate a lot of heat, such as high-speed cutting, drilling, etc., if the heat generated cannot be taken away by the cutting fluid in time, the phenomenon of sticking to the knife will occur, and even built-up edge will appear, which will seriously affect the quality of the workpiece. Machining roughness and the service life of the tool, at the same time, the heat will also deform the workpiece, which seriously affects the accuracy of the workpiece. Therefore, the choice of cutting fluid should consider not only its own lubricity, but also its cooling performance.
For grinding, the grinding chips are very fine, and a lot of heat will be generated during the grinding process. Therefore, when choosing a cutting fluid, it is necessary to consider not only the lubrication and cooling performance, but also the filterability of the cutting fluid. If the viscosity of the selected cutting fluid is too large, the chips cannot be deposited or filtered out in time, then the surface of the workpiece will be scratched as the cutting fluid circulates to the processing area, thus affecting the smoothness of the processed surface. Therefore, low-viscosity anti-friction grinding oil or semi-synthetic anti-friction cutting fluid is selected for fine grinding or ultra-fine grinding.
In the selection of cutting fluid, in addition to the lubricity and cooling properties of the cutting fluid, the rust resistance, cost and easy maintenance of the cutting fluid should also be considered. Cutting oil is easy to use base oil with relatively low viscosity to add anti-friction additives, which can not only achieve lubrication and anti-friction, but also have good cooling and easy filterability. However, the problem of cutting oil is low flash point, heavy smoke during high-speed cutting, high risk factor, and fast volatilization, which will increase the user cost accordingly. Therefore, if conditions permit, try to use water-soluble cutting fluid.

For water-based cutting fluid, it is more important to consider its rust resistance. The commonly used water-based aluminum rust inhibitors include silicates and phosphate esters. For workpieces that have been stored for a long time between processes, it is easy to use cutting fluids with phosphate ester-type rust inhibitors during processing, because silicon and aluminum are long-lasting. Corrosion occurs with time exposure to produce black "silicon spots". The pH value of the cutting fluid is usually kept at 8-10. If the rust resistance is not good, aluminum is easily corroded under such alkaline conditions. Therefore, the water-soluble cutting fluid must have good aluminum rust resistance.

The use and maintenance of cutting fluid for seamless aluminum tube processing
The preparation and use of cutting fluid for seamless aluminum tube processing is basically the same as that of ordinary cutting fluid, except that the selection of dilution water is more stringent. Because many ions in water can corrode aluminum, if the content of these ions is too much, the antirust performance of the cutting fluid will be reduced, especially in the antirust between processes, such as chloride ions, sulfate ions and heavy metal ions. In addition, some ions will react with the aluminum antirust agent in the cutting fluid to reduce the rust resistance and stability of the cutting fluid, such as calcium and magnesium ions. Therefore, try to choose dilution water with less hardness, or dilution water softened by ion exchange, to ensure the use effect and service life of the cutting fluid.
In addition to the daily maintenance of ordinary cutting fluid, the maintenance of cutting fluid for seamless aluminum tube processing also needs to pay attention to the following points:
1. Filter
Because the seamless aluminum tube is easy to react under alkaline conditions to form aluminum soap, which will damage the stability of the cutting fluid, so the cut aluminum scrap should be filtered out immediately to avoid the reaction between the aluminum scrap and the cutting fluid and affect the cutting fluid effect and service life. The aluminum shavings that are ground out during the grinding process are small and light, and are difficult to settle. If there is no filtration or insufficient filtration, the aluminum shavings will be brought to the processing area along with the cutting fluid circulation system and scratch the surface of the workpiece. , affecting the glossiness of the machined surface.
2. pH value
Because the aluminum material is very sensitive to the pH value of the cutting fluid, the pH value of the seamless aluminum tube cutting fluid should be checked frequently, and any abnormality should be adjusted in time. The pH should be controlled at 8-9, so as not to corrode the workpiece if the pH value is too high or cause bacteria to proliferate if the pH value is too low, which will affect the stability and performance of the cutting fluid.
3. Regularly add new liquid
It not only ensures the good lubrication of the cutting fluid, but also ensures the good anti-rust performance and anti-bacterial and anti-corrosion performance of the cutting fluid, so as to prolong the service life of the cutting fluid.
Conclusion
The choice of cutting fluid for seamless aluminum tube processing is very important. It is necessary to ensure good lubricity and rust resistance of the cutting fluid, as well as good stability, filterability and easy maintenance. Only in this way can the processing meet the requirements. The product can minimize the use cost of cutting fluid.