The maximum inclination angle of a herringbone conveyor belt is a key design parameter, determined by considering material properties, pattern design, and conveying conditions. The following is a systematic summary and supplementary explanation:

I. Conventional Herringbone Conveyor Belt Incline Range
General Materials (Sand, Gravel, Coal, Ore, etc.)
Angle Range: 17°-28°
Applications: Dry or slightly damp bulk materials, relying on the anti-slip properties of the herringbone pattern to improve conveying stability.
High-Friction Design (Deep Pattern or Special Rubber)

Upper Angle Limit: Can be increased to 30°-35°
Example: Reinforced herringbone belts utilize a deeper pattern or high-friction rubber surface to handle sticky materials.

II. Special Materials and Extreme Angles
Wet and Sticky Materials (Wet Sand, Clay, etc.)
Extreme Angle: 35°-40°
Technical Support: Requires use of a high-frequency anti-stick coating (such as polyurethane) or a dynamic cleaning device (such as a scraper) to prevent material retention.

Ultra-inclined Solution
Skirted baffle belts: Angles can reach 60° to 90°, but this requires sacrificing belt width and speed, and has strict requirements on baffle height and spacing.
Corrugated sidewall belts: Increased lateral rigidity makes them suitable for continuous conveying at large inclination angles (≤ 90°), but at a higher cost.

III. Key Influencing Factors
Material Properties
Angle of Repose: The theoretical limit is determined by the natural angle of repose (for example, quartz sand has an angle of repose of ≈34°, but practical conveying requires ≤30°).
Moisture/Viscosity: Wet materials should be reduced by 5° to 10° to prevent slippage or sticking.
Belt Design
Tread Depth: Each 1mm increase in depth increases the inclination by approximately 1° to 2° (but excessive depth can lead to material accumulation).
Rubber Surface Material: Wear-resistant, high-friction rubber (such as an SBR/NBR blend) offers a 3° to 5° higher inclination than standard rubber.

Operating Parameters
Belt Speed: For speeds > 2 m/s, the inclination angle should be reduced by 1° to 2° for every 0.5 m/s increase to prevent spillage. Load Rate: At full load, it is recommended to reduce the nominal maximum angle by 10%-15%.

IV. Selection Process
Measure the material’s angle of repose, moisture content, and particle size distribution.
Calculate the belt speed and belt width based on the conveying volume to preliminarily determine the inclination angle range.
Adjust the angle based on the equipment layout (horizontal and vertical section lengths).
Through scientific selection and design, a herringbone conveyor belt maximizes space utilization within a safe range, balancing efficiency and reliability.