What cutting fluid is more suitable for rough machining?

Depending on what materials you are processing, of course it is water-soluble for cost reasons.

1. Broaching

Broaching includes a series of low-speed, shallow Cutting operations have lower temperatures than other operations. People often only use chlorine as an extreme pressure additive because the lower temperatures in the cutting zone often prevent sulfur from being effective. On the other hand, it is quite difficult for cutting oil to come into contact with the cutting area, so the cutting oil must be selected to have a very low viscosity so that they have good permeability and moisturizing properties.

If you are broaching a metal that is easy to process, you can use water-soluble cutting oil or oily cutting oil with a slight chlorine content. For more difficult-to-machine metals, such as heat-resistant steel, constant shallow cuts harden the surface of the steel, so we must use a cutting oil containing high extreme pressure additives. Water-soluble cutting oils are too dilute to contain sufficient extreme pressure additives. Therefore, we often choose to use oily cutting oils with low viscosity and containing a large amount of chlorine additives.

2. Gear cutting and hobbing processing

In gear cutting and hobbing processing, the cutting tool and chips are under great pressure. In this kind of processing, the lubrication effect of the cutting area is The most important thing. For some easy-to-cut steels and metals that are easier to process, we can use water-soluble cutting oil or oil-based cutting oil. However, for some metals that are difficult to machine, such as high-tensile nickel, chromium, or other alloys, water-soluble cutting oil cannot be used. The correct choice should be an oil-based cutting oil containing many extreme pressure additives.

3. Drilling

The cutting oil suitable for drilling should have lower viscosity and lower surface tension, and can fully penetrate into the cutting area and at the same time Take out the waste. When drilling holes in easily machined metals, we can use water-soluble cutting oils or synthetic cutting fluids. For some metals that are difficult to machine, only low-viscosity oil-based cutting oils containing extreme pressure additives can be used.

4. Turning and milling

Turning and milling are medium-load machining operations and one of many single-point machining operations. Generally speaking, there are no special problems with these two machining operations. The best way to choose cutting oil is based on the material being processed.

Take cast iron as an example. This material is easy to process and can even be processed without cutting oil. Using cutting oil can reduce its temperature, but its biggest function is to carry away cutting waste. The lubrication effect of cutting oil is not very important. It is enough to use water-soluble cutting oil or synthetic cutting fluid.

If it is turning or milling of metals that are moderately difficult to process, such as easy-to-cut low carbon steel, a high lubrication effect is required, and the cutting chips also need to be taken away. For this type of metal, traditional emulsion can be used Water-soluble cutting oil or grease-containing low-viscosity mineral oil.

If it is very difficult to process metals such as stainless steel, nickel and cobalt alloys, high heat will be generated during processing, so the cutting oil should contain sulfur and chlorine. It is advisable to use water-soluble cutting oil containing extreme pressure additives. Or oily cutting oil. Oily cutting oil should have medium viscosity, and the cutting oil can achieve the best balance in penetration and lubricity.

5. Grinding

From the perspective of cutting oil, grinding is like a series of small high-speed cutting processes, so it is sometimes called multi-point cutting. The temperature is quite high, and most of the heat at high temperature is absorbed by the workpiece. Cooling is very important for grinding processes. High temperatures, if not properly controlled, can change the shape of the workpiece. In addition, cutting oil must have detergent and good moisturizing effect. It can penetrate into the grinding area to remove the grinding debris on the grinding wheel, and prevent the grinding wheel from becoming smooth and losing its grinding effect. At the same time, it can make those small chips and impurities easily separated from the cutting oil.

Some metals that are easy to process, such as cast iron and free-cutting steel, are easy to grind. We generally use some transparent water-soluble cutting oil or synthetic cutting fluid. The main purpose of these cutting oils is to lower the temperature of the workpiece, keep the grinding wheel clean, and remove grinding and metal chips during processing; at the same time, it prevents the workpiece from rusting and corroding before and after grinding.

Grinding some more difficult metals, such as stainless steel and high-nickel alloys, these metals are known to stick because at very high temperatures, these metals will corrode and the friction particles attached to the grinding wheel will on, thus causing the grinding wheel to become smooth and lose friction.

In order to avoid this situation, cutting oil should not only have cooling and cleaning functions, but also lubrication functions. Therefore, chlorine and sulfur extreme pressure additives should be added to the grinding cutting oil. Sulfur is particularly important here because when the grinding wheel rubs against the workpiece, the temperature is quite high.

For these more difficult metals, water-soluble or oily cutting oils containing the above additives are often used. The base oil viscosity of oil-based cutting oils should be very low to ensure that it can penetrate, cool, and carry additives to the grinding area.

In grinding processing, the quality of finished products is greatly affected by cutting oil. In generally rough grinding operations, the main purpose of processing is to remove a large amount of metal. In this case, the cutting oil requires less lubricating properties and greater cleaning ability to ensure the cleanliness of the grinding wheel. Applicable products are transparent water-soluble cutting oils or synthetic cutting fluids.

For grinding processes that require very good quality of finished products, the cutting oil should have more lubrication effect. You can choose to use water-soluble cutting oils or low-viscosity oil-based cutting oils that contain more additives and higher concentrations.