In a recent series of tests, the feeding performance of our devices was examined for very small target quantities. The goal was batch feeding of 60 mg of powder with a permissible tolerance of ±3 % for a future project.
The aim of the tests was to achieve a batch weight of 60 mg (0.06 g) with a maximum deviation of ± 1.8 mg. The aim was to test the technical feasibility and process reliability for this small quantity for a future customer project. A fine-grained semolina with a grain size of less than 300 µm, which is comparable to the customer's original product, was used for the tests.
We used the smallest feeding device in our portfolio, a ZD 5 FB flat-tray feeding device, which continuously weighed the discharged quantity using a high-resolution load cell and adjusted the screw speed accordingly. The tests were carried out in our test laboratory under stable environmental conditions in order to minimize external influences.
The tests were successfully completed: the feeding values achieved were within the tolerance range of ±1.8 mg. This confirmed that the device also works precisely and repeatably in the low milligram range. The measurement results also showed that fine adjustment of the parameters can achieve stable feeding performance across multiple batches. Fluctuations in material flow or bulk density had only a minor effect on the result.
Measurement results of the tests (weight/time)
Three of the high-precision feeding devices will be integrated into a customer's production line in the future. These devices complement the process by adding a small amount of powder to pre-filled containers. The integration is both mechanical and control-related. The devices can communicate directly with the plant control system via standardized interfaces. This allows the feeding process to be carried out automatically and reproducibly. The compact design of the devices allows for easy integration into existing plant structures.
60 mg fed material
ZD 5 FB flat-tray feeding device