How to choose abrasive discs with different particle sizes for coarse grinding, fine grinding and polishing?

In floor treatment, stone processing or surface repair work, the particle size of the abrasive disc directly affects the construction effect and efficiency. It is crucial to choose the appropriate particle size according to the specific construction stage (coarse grinding, fine grinding or polishing). The following will elaborate on how to choose the appropriate abrasive disc from three aspects: the classification of particle size, the requirements of different grinding stages, and specific application scenarios.

1. Classification and significance of particle size
The particle size of the abrasive disc is usually expressed in "mesh number" (#). The lower the mesh number, the larger the particle size and the stronger the grinding ability; the higher the mesh number, the finer the particle size and the finer the surface treatment effect.

Low mesh number (30#-60#): used for coarse grinding to quickly remove the hard layer or irregular parts of the surface.
Medium mesh number (80#-150#): used for fine grinding to reduce scratches left by coarse grinding and prepare for the polishing stage.
High mesh number (300# and above): used for polishing to improve the surface gloss and fineness.
2. Particle selection in the coarse grinding stage
Coarse grinding is the basis of the entire grinding process. Its main purpose is to remove surface impurities and repair the height difference or damaged parts of the ground.

It is recommended to use 30# or 50# grinding discs. Their large particles can efficiently remove excess materials and significantly improve construction efficiency.
For hard floors (such as concrete floors above C30), you can choose grinding discs with higher sharpness to ensure smooth cutting.
3. Particle selection in the fine grinding stage
The main task of the fine grinding stage is to eliminate the deep scratches left by coarse grinding and create a smooth base for surface polishing.
80# to 150# medium-grained grinding discs are the first choice for fine grinding. They can effectively smooth the surface while maintaining a certain grinding ability.
Depending on the hardness of the ground and the required smoothness, grinding discs of different meshes can be used gradually to complete the transition.
4. Particle selection in the polishing stage
Polishing is a key stage to improve the gloss of the ground, and high-mesh grinding discs are required for fine grinding.
300# and above grinding discs can effectively remove tiny scratches and improve surface brightness and texture.
When dry grinding or wet grinding and polishing, you can choose whether to use polishing liquid according to the construction requirements. For grinding discs that do not require polishing liquid, it can further save construction time and cost.
5. Recommendations for different application scenarios
Industrial floor: mainly based on wear resistance, it is recommended to choose low-mesh grinding discs for rough grinding, and adjust the mesh according to needs during polishing.
Warehouse floor: it is necessary to take into account both smoothness and durability. It is recommended to use medium-mesh grinding discs in the fine grinding stage to ensure flatness without over-polishing.
Parking lot floor: it has high requirements for anti-slip and durability, usually focusing on rough grinding and fine grinding, and polishing should not be excessive.