Function of Grinding Liquid
During the grinding operation of roll grinding machine, due to the internal friction of the deformation of the roll and the external friction between the grinding wheel and the roll, a large amount of grinding heat will be generated, and the maximum temperature in the grinding area can sometimes reach about 1000 °C. The high temperature generated by grinding can cause burns and cracks on the surface of the roll. Therefore, cooling during roll grinder's working is very important.
Grinding liquid can play the following roles:
(1) Cooling - through the heat conduction effect of the grinding liquid, it can effectively improve the heat dissipation conditions, take away most of the grinding heat, and reduce the temperature of the grinding area.
The cooling effect is related to the type, performance, dosage, and method of use of the grinding liquid. The greater the thermal conductivity coefficient of the grinding liquid, the more significant the cooling effect. For example, the cooling of water is much stronger than that of oil.
(2) Lubricating - After the grinding liquid penetrates into the contact surface of the grinding debris, abrasive grains and roll, it adheres to the metal surface to form a lubricating film, which can reduce the friction between the abrasive grains and the roll, and reduce wear debris bonding with abrasive grains, thereby improving the quality of the roll surface and the life of the grinding wheel.
Due to the high pressure on the contact surface, pure mineral oil is not easy to penetrate into the grinding area. Therefore, some extreme pressure additives such as sulfur, chlorine, and phosphorus are added to the general grinding liquid. These additives can undergo rapid chemical changes after contact with steel and iron surfaces. Produce new compounds (ferric sulfide, ferric chloride, etc.), adsorbed on the metal, which can significantly improve the lubrication effect.
(3) Cleaning- the grinding liquid can wash away the wear debris and the broken abrasive particles, preventing the grinding surface of the roll from being scratched.
(4) Anti-rusting - After adding anti-rust additives to the grinding liquid, a protective film can be formed on the metal surface to protect the roll and CNC roll grinder from oxidation and play an anti-rusting role.
According to the function of the grinding fluid, the grinding liquid should meet the following requirements:
The chemical composition of the grinding liquid should be pure and should not contain toxic impurities. The pH value of the acidity of the grinding liquid should be neutral, so as not to corrode the roll, roll grinding machine and irritate the human skin; it is not easy to deteriorate; The vitrified bond is not eroded by the grinding liquid, the resin bond is easily eroded by the alkaline grinding liquid, and the rubber bond is easily eroded by the oily grinding liquid.