Ratholing is a well-known phenomenon in powder handling. Instead of the entire hopper content moving towards the outlet, only a narrow channel above the discharge point becomes active, while the surrounding material remains stagnant. This results in irregular flow behaviour, segregation and unpredictable dosing performance.
A clear example of this can be seen when handling Katechu powder. This material is known for its cohesive and sticky properties, making it difficult to process using conventional feeding systems. Without proper flow stimulation, the powder tends to form stable structures that prevent consistent discharge.
To demonstrate this behaviour, HETHON conducted a practical test showing how ratholing develops in Katechu powder and how it can be effectively resolved.
In the first part of the test, the material forms a stable rathole, where only a limited portion of the powder is flowing. The majority of the product remains stationary, which would lead to severe dosing inaccuracies in a real production environment.
In the second part, controlled external agitation is applied to the hopper. Instead of using internal mechanical devices that may damage the product or cause contamination, the HETHON solution activates the material from outside the hopper wall.
This approach ensures that the entire bulk mass is mobilised, eliminating ratholing and restoring a consistent and uniform material flow. As a result, dosing becomes stable, predictable and accurate, even for challenging materials like Katechu powder.
Another advantage of external agitation is that it prevents product degradation. Sensitive powders remain intact, while the system itself remains low-maintenance and easy to clean.
For industries dealing with difficult powders — such as food, chemical or pharmaceutical processing — this approach offers a reliable solution to improve both efficiency and product quality.
HETHON’s experience with materials like Katechu powder demonstrates that even the most challenging flow problems can be solved with the right combination of engineering and practical testing.
