Technologies applied in polymers processing are permanently improved due to updating the knowledge on material proprieties, processes and phenomena during the processing. To determine the pressure distribution, one should define the geometrical shape of a channel, in the flow will be held the flow. The aim of calculations carried out is to determine the possibility of mathematical modelling of polymer flows between conical parallel surfaces. In this work, the flow of a polymer in conical channels was considered. To describe a melted polymer the model of a viscoplastic fluid was used but final results were illustrated by a flow of the Bingham fluid. The Bingham fluid chosen to modelling the flow of a polymer may by considered as legitimate, because its use will allow us to illustrate analytical methods of calculations. For the flow configuration and model under consideration the geometrical sizes of the channel and material coefficients of the fluid will be chosen on the basis of experimental data contained in literature. In the article, the on defining dimensionless pressure distribution for the flow in a conical channel as well as in a conical annular channel with the influence of inertia were presented. The results of calculations were introduced in tabular forms as well as in graphic forms.