
Belt dryers are widely used for drying foods, herbs, vegetables, and chili peppers. One important design parameter is the mesh size of the belt. Many customers ask: Why are most belt dryer meshes 3mm? Let’s explain.

The Role of Mesh Size
The belt serves as both the carrier and support for the material. The mesh size directly affects:
Airflow and heat efficiency
- A larger mesh allows hot air to pass through more easily, increasing drying speed.
- A smaller mesh can block airflow, causing uneven drying or localized moisture retention.
Material support and stability
- A smaller mesh provides better support for thin or granular materials.
- Too large a mesh can allow light or thin items to fall through, reducing yield and safety.
Material adaptability
Different materials require different mesh sizes to balance airflow and stability. Whole chili peppers, vegetable slices, or herbal slices all need adequate support without compromising drying efficiency.

Why do Our Machines Use a 3mm Mesh?
For example, in our SL Series Belt Dryers:
Parameter | Value / Description |
---|---|
Mesh size | 3mm |
Suitable materials | Chili, vegetable slices, herbal slices, nuts |
Drying thickness | 10–80 mm (adjustable) |
Drying efficiency | High-efficiency airflow penetrates evenly for uniform drying |

Reasons
Balance airflow efficiency and material support
- 3mm allows hot air to pass efficiently while keeping thin or granular materials stable.
Adaptable to a wide range of material thickness
- Our belts handle 10–80 mm thickness; 3mm is the optimal compromise.
Easy cleaning and durability
- A smaller mesh can clog and is harder to clean; a larger mesh reduces strength. 3mm strikes a good balance.
Industry experience
- Years of experience in food and herbal drying show that 3mm is the most practical and universal mesh size.

Conclusion
The 3mm mesh is chosen based on:
- Balancing drying efficiency and material support
- Suitable for a wide range of material thickness
- Easy to clean, durable, and low maintenance
- Proven effectiveness in real-world applications
In short: 3mm is the golden mesh size for belt dryers, balancing efficiency, stability, and durability — the reason why it is widely used in our SL Series machines.
Custom meshes with smaller sizes can also be provided for extremely thin or small materials, based on your specific process needs.
