During the grinding process of the sand mill, it is easy to encounter the phenomenon of grinding color paste not meeting the requirements, which will bring us unnecessary resource waste to ensure the interests of customers. In order to better meet the needs of users in grinding color paste, we continuously identify the reasons from practical operations, so as to achieve the required fineness of grinding color paste and improve work efficiency. Therefore, the author analyzes the reasons why color paste grinding cannot meet the requirements and proposes solutions. The reasons why the grinding paste of the sand mill cannot meet the requirements are as follows:

1. The fineness of the pigment itself is greater than the required fineness of the color paste and cannot be ground. In many cases, it is caused by the original particles of the pigment being greater than the required fineness of the color paste. The solution is to further process and crush the pigment to make its particle size below the required fineness of the color paste, as the dispersion process of the color paste grinding cannot solve the problem of further reducing the original particles;

2. The pigment contains a large amount of impurities and cannot be finely ground, such as impurities such as paint, fibers, dust, and fine sand particles. The solution is to first rely on the pigment supply department to strengthen management, strictly prohibit the mixing of impurities, and ensure product quality; Secondly, when pairing in the color paste production workshop, it is necessary to strengthen the filtration of paint materials and pay attention to the timely removal of identifiable impurities in the powder; When using three rollers to disperse the impurities that have already been mixed, full or residual bucket operations should be taken, or a single roller mill should be used in series to fully filter the slag;

3. The pigment particles are tightly packed and difficult to disperse, such as carbon black and iron blue. When encountering this situation in production, the following measures should be taken: firstly, the process should be adjusted reasonably. For example, the sand grinding dispersion process can be carried out through ball milling or three roll grinding, followed by sand grinding dispersion; The second is to use dispersants, and other solvents such as carbon black for pre impregnation can also improve dispersion efficiency. The above methods may have an impact on production, so it is fundamental to carry out surface treatment of pigments to improve grinding and dispersion performance.

4. The fineness of the paint paste itself cannot meet the requirements of the color paste, and the fineness of the paint paste must meet the specified fineness standards, otherwise the fineness of the color paste will not be guaranteed