Oleic acid and Tall Oil are common fatty acid additives in Cutting fluid. Oleic acid is divided into two types: plant oleic acid and animal oleic acid, with animal oleic acid being the best quality. In addition, petroleum olefins can also be used to produce oleic acid, which is currently less commonly used. Refined high-purity oleic acid appears as a colorless to light yellow oily liquid, while industrial products are mostly in the form of paste or fat. The components of various oleic acids are not completely the same, and there are significant differences in indicators such as iodine value, acid value, and freezing point. The color and odor also vary greatly, and the price also varies accordingly. Oleic acid contains active double bonds and is easily oxidized by air, resulting in a bad odor and yellowing in color. Refined vegetable oleic acid is a light colored transparent liquid with a low pour point of industrial oleic acid. It is a greasy and layered oil at room temperature, commonly referred to as Distilled Tall Oil (DTO). Commonly used grades generally contain about 70% of Tall oil fatty acids, about 30% of rosin acid, and some unsaponifiable substances, thus greatly different in properties from oleic acid. In addition, pine trees from different regions, such as those in the cold, subtropical, and tropical regions, have different DTO performance.
In summary, there is a significant difference in performance between oleic acid and tall oil, and users can flexibly choose according to different formula design ideas, application purposes, cost requirements, etc. Selecting oleic acid can selectively generate hard water soap, which plays a role in defoaming and lubricating efficiency enhancement (provided that the soap can be evenly dispersed, rather than sticking to the inner wall of the machine tool or floating on the surface of the tank liquid); Choosing tall oil can greatly reduce the production of hard water soap, making it a good choice in northern and western regions with higher water hardness.
