<p>Vibratory finishing is widely used in aerospace, weapon industry, high-grade computer numerical control machine tools, rail transportation equipment, and other high-end equipment manufacturing industries. Processing parameters are critical to processing efficiency and processing effect. Island-less bowl vibratory finishing equipment is commonly used to process medium and large disk parts. Compared with traditional bowl vibratory finishing equipment, the lack of an island structure in the shape of the container and the low motor mounting position can lead to changes in the container motion and the flow field of the particulate medium. In this work, a bowl vibratory finishing mathematical model and numerical model were established, the velocity of the granular media at different locations in the container and the magnitude of the force was analyzed, the change rule of the container amplitude size, granular media motion characteristics and force behavior under different processing parameters was elucidated, the container amplitude test experiments and the force test experiments were carried out. The results show that during bowl vibratory finishing, the container performs periodic three-dimensional elliptical motion in space. The lack of island structure in island-less bowl vibratory finishing results in lower motion speed and frequency of the granular media in areas far away from the container wall. The granular media makes a spiral motion around the container’s central axis consisting of circular and tumbling motions in an extended period and performs irregular velocity-changing annular spiral motion in a short period. The phase difference will change the motion direction of the granular media. The mass of the upper eccentric block affects the intensity of the circular motion of the granular media, and the mass of the lower eccentric block affects the intensity of the tumbling motion of the granular media. Selecting a phase difference of 90°, increasing the motor rotational speed and the eccentric block’s mass can increase the granular media’s velocity and force. This study provides a reference for improving processing efficiency and changing granular media flow field motion.</p> Graphical Abstract <p></p>