The grinding of oilseeds intended for nutritional purposes is a complex technological process. Due to strictly defined requirements regarding the size of the particulate particles and the temperature prevailing during the grinding process, it is necessary to determine the optimal parameters of the working system, such as the shape of the cutting tool, the angular velocity, the material feed rate or the vacuum value prevailing in the grain transport system. The article discusses a precise grinding system, with particular emphasis on the part responsible for pneumatic transport of shredded grains. The model of the system based on the results of measurements of negative pressure prevailing in the installation for different angular velocities of the cutting tool is presented.