In the process of rolling steel (mainly cold rolling), in order to reduce the friction between the roll and the rolling material, reduce the rolling force and power consumption, make the rolling material easy to extend, control the rolling temperature, and increase the quality of the rolled product. Lubricating coolant is added between the contact surface of the roll and the rolling material. This process is called rolling process lubrication.

Cold rolling is usually performed by hot rough rolling and finishing rolling to obtain a steel coil with a thickness of 2 to 4 mm, which has been pickled and annealed. It is rolled by a multi-roll mill (reversible or continuous rolling) to a thickness of 0.8 mm to 0.01. mm sheet. Due to the large deformation resistance of cold metal, the rolling force of modern cold rolling mills has reached thousands of tons, and the rolling speed is close to 2500 m / min. Obviously, during such a high-speed deformation process of the metal, on the one hand, a large amount of thermal energy is generated due to the friction between the molecules inside the metal; on the other hand, the reduction (extension) of the rolling material cannot evade the relative movement of the roll and the surface of the rolling material .

The basic requirements for cold rolling lubricants are:

1. Appropriate oiliness, that is, the boundary oil film can still be formed under large rolling pressure to reduce friction resistance and resistance to metal deformation; reduce roller wear and increase roller service life; increase rolling reduction, reduce rolling passes, and save energy consumption. However, it is necessary to consider the friction between the roller and the steel from time to time to make the steel bite into the roller. The friction coefficient is too low and it will slip. So the lubrication performance is appropriate

2. Good cooling ability, that is, it can absorb the heat generated in the rolling process to a maximum extent and achieve constant temperature rolling to maintain the roll with a stable roll shape and keep the strip thickness uniform;

3． Good rinsing and cleaning effect on roll and strip surface. In order to remove impurities and dirt mixed in from the outside, increase the surface quality of steel;

4． Good physical and chemical stability. During the rolling process, it does not react with the metal and does not affect the physical properties of the metal;

5. Good annealing performance. In modern cold-rolled strip production, in order to simplify the process, increase labor productivity, and reduce costs, when intermediate annealing is required, the production process of direct annealing without degreasing and cleaning is adopted. This requires that the lubricant is not annealed and corroded due to its residual on the surface of the steel (ie, spots on the surface of the steel);

6. Filtration performance is good. In order to increase the surface quality of steel, some rolling mills use high-precision filtering devices (such as diatomaceous earth) to largely remove impurities from the oil. At this time, it is necessary to avoid the additives in the oil from being adsorbed or filtered to maintain the quality of the oil;

7. Good oxidation stability and long service life;

8. Good rust resistance. For short-term storage between processes, it can play a good role in rust prevention;

9. It should not contain substances harmful to human health and irritating odors;

10． Oil source, easy to obtain and low cost.

Hot rolling process lubrication

Increasing the output of hot-rolled strip mills, reducing consumption, and increasing productivity are important things in the rolling process. Practices in various countries have proven that the use of hot rolling oil can reduce roll wear, reduce power consumption, improve the surface quality of steel plates, and increase productivity.

The following benefits can be obtained with hot rolling (as proven in practice):

1. Improved surface condition of the roll.

2. Reduced unit consumption of rolls.

3． Reduced power consumption.

4． Increased surface quality of the strip.

5. Reduce rolling pressure and easily roll thin gauge strips.

6. Promote research on hot rolling theory.