A filling shoe – typically rectangular and milled from metal – is a key component in any powder press. It is either supplied with the machine or manufactured in-house.
At ROBOWORKER, our experts have taken a closer look at the function of the filling shoe in powder compaction. Their findings show that both the geometry and the material of the filling shoe play a crucial role in the quality of the compact. When combined with a perfectly matched powder press, optimizing the filling shoe can significantly improve shape accuracy, density distribution, and repeatability.
In rectangular filling shoe designs, powder often collects in the corners and doesn’t immediately transfer to the cavity.
As the filling shoe moves back and forth, this residual powder is shaken, which can degrade its consistency and lead to powder segregation, where powder particles of different sizes separate. If these segregated particles enter the cavity, it can cause density fluctuations in the pressed part, compromising its quality.
With a well-thought-out design that enables optimal centering of the powder, the specialists at ROBOWORKER have achieved an innovative development. The powder volume in the chamber can be reproducibly adjusted via the filling tube, ensuring consistent density. Additionally, we have integrated an extraction system into the filling shoe.
ROBOWORKER produces filling shoes using cutting-edge manufacturing technologies in our own 3D printing center. This modern production method allows for a highly flexible design and rapid production at attractive prices.
We place particular emphasis on the surface quality of the filling shoes. The combination of plastic components and CNC-manufactured parts ensures optimal powder flow behavior and guarantees absolute density and chemical resistance, allowing for frequent cleaning, including in ultrasonic baths. We test these properties under demanding test conditions on our own powder presses.
With well-designed adapter kits for connecting the filling shoe to various flange diameters on the powder silo or to custom filling forks, ROBOWORKER enables the use of its filling shoes on all standard presses, not just its own.
For test series or small batches, ROBOWORKER has developed mini powder hoppers that can be easily attached, removed, and cleaned quickly.
