Grinding belts are a commonly used tool for surface treatment of materials such as metal, wood, and plastic, and the coarseness level is one of the important factors affecting the processing effect.
When selecting grinding belts, it is necessary to choose different coarseness levels according to the specific processing material and processing requirements.
This article will introduce and analyze aspects such as roughness, granularity, and grinding methods, to help readers better understand and choose grinding belts.

Roughness
The roughness of a sanding belt refers to the unevenness of the belt surface and is generally expressed as an Ra value. A smaller Ra value indicates a smoother surface of the sanding belt and better processing results. Generally, there are several types of roughness for sanding belts:
High gloss grinding belt
High gloss grinding belt is a type of surface treatment belt with very low roughness, indicating a smoother surface and better processing effect with smaller Ra values. It is generally used for final product processing to achieve high-quality surface glossiness. High gloss grinding belts usually use silica-based particles with a grit size above 800#, requiring low-speed operation and high-quality grinding oil or grinding agent for optimal results.
Polishing grinding belt
Polishing grinding belt is a premium type of grinding belt with an extremely smooth surface and low roughness. Its grit size is usually above 800#, and high-quality grinding agents are required for use. It is ideal for surface treatment of high-demand products.
Semi-gloss grinding belt
Semi-gloss grinding belt has a roughness between high gloss and polishing grinding belts, with a grit size usually between 400# and 800#. It is generally used for optimizing the surface of products to achieve a certain level of glossiness and smoothness. Semi-gloss grinding belts have a higher grit size and better grinding effect, but slower grinding speed. Therefore, it is necessary to choose the appropriate semi-gloss grinding belt based on the specific processing material and requirements.
Particle Size
The grit size of a grinding belt refers to the size of abrasive particles, usually represented by mesh number, which indicates the number of particles per inch. The higher the mesh number, the finer the abrasive particles.
Based on grit size, grinding belts can be divided into three types: coarse grit, medium grit, and fine grit.
Usage | Abrasive Grain Size | Grit | |
coarse grit | Generally used for initial surface treatment and trimming, and for repairing and processing products with significant surface defects. | Coarse | Usually between 36#-80# |
medium grit | Usually used for surface optimization treatment. | Fine | Usually between 100#-240# |
fine grit | Usually used for precision machining and surface treatment. | Very Fine | Usually between 320#-1200# |
The processing effect of the medium sand belt is better than that of the coarse sand belt, which is more suitable for processing products with higher requirements for surface smoothness and evenness. The processing effect of the fine sand belt is the best, which is more suitable for processing products that require extremely high surface smoothness and evenness.
Grinding Methods
The grinding method of the abrasive belt mainly includes manual grinding and mechanical grinding.
Usage | Speed | Precautions, | |
manual grinding | Mainly carried out by manual grinding machines, but it can also be used for local and fine processing. | Slow | Attention needs to be paid to operating skills and the use of sand belts to avoid the decline in processing quality due to improper operation. |
mechanical grinding | It is mainly carried out by automatic grinding machines, which have high processing efficiency and are suitable for mass production. | Fast | It is necessary to select appropriate sanding belts and grinding parameters to achieve the best processing results. At the same time, regular maintenance and upkeep of the grinding machine are required to ensure machine stability and consistency in grinding quality. |
Conclusion
It is worth noting that manual grinding and mechanical grinding have their respective applicable processing scenarios, and the selection should be based on specific processing needs and material characteristics. In practical applications, some processing scenarios require a combination of manual and mechanical grinding to achieve better processing results.
In summary, the choice of grinding method for grinding belts directly affects processing quality and efficiency. It is necessary to select and apply the appropriate method based on processing requirements and material characteristics, and to pay attention to operating skills and equipment maintenance.