Reliable storage, handling and dosing are essential at processing and manufacturing of ultrafine powders. The powder flow in a silo can be hindered by bridging or channeling. The excitation of mechanical oscillations by vibrating hopper has been proved to solve this flow problem. The minimum outlet width and wall friction are clearly reduced by this excitation of oscillations during the shear test. Next, these lab-scale design data are proven at pilot-scale silos. The influence of frequency and amplitude of oscillations on powder flow was investigated.