In this paper, a rotary vane feeder with adjustable speed is proposed to uniformly and stably convey steel particles from a storage vessel into a pipe line under high pressures of up to 30 MPa. A structural stress analysis of the rotary vane feeder was carried out in ANSYS Workbench and a field-scale three-dimensional apparatus was then developed to perform conveying experiments under various operating parameters according to specific applications. Furthermore, a model was established to evaluate the particle feeding rate by using a data fitting method and was experimentally validated. For the same conditions, particle feeding rates calculated using the model were found to be consistent with those experimentally obtained. Motor power increased linearly with the rotational speed of the vane, however, motor torque remained almost unchanged. The particle feeding rate was found to rapidly increase at rotational speeds lower than 30 r/min. Moreover, the particle feeding rate increased as the particle diameter increased, and decreased as the barrel pressure increased. The particle feed per revolution also decreased with increasing vane rotational speeds, whereas the feed was shown to increase as the particle diameter increased. In addition, the particle feed per revolution was smaller at a barrel pressure of 25 MPa compared to 0.1 MPa. Erosion caused by particles impacting the wall of the vane was mainly concentrated on the exterior wall of the vane away from the axle. Finally, the optimal rotational speed required to maximize the particle filling efficiency was found to be 28 r/min. (C) 2019 Elsevier B.V. All rights reserved.