FEATURES OF THE FLOW OF THERMAL PROCESSES IN THE MACHINE FOR BELL FORMATION IN POLYPROPYLENE TUBES

The results of computer modeling of thermal processes in the machine for the formation of a bell in pol-ypropylene tubes are presented. A feature of the providing machine is the presence of two working zones. In the first zone, polypropylene tubes are heated, and their plastic deforming is performed in the second zone. In each zone, individual thermal models are implemented in transient in the start. Two problems were solved in the warm -up zone. The solution of the first problem allowed the dumping-pouring algorithm for the heating of the heating elements used to ensure the trendy temperature of the deformable section of the tube. The solution of the second problem made it possible to determine the emerging temperature extensions of both the heated section of the tube and the expansion of the internal and outer furnaces for two sizes of the tubes. In the plastic deformation zone, the results of computer modeling for two models are also presented. The first model considered the supply of cooling water into stamps and a mandrel. In the second model, on the contrary, the option of warming up stamps and mandrel was investigated. A feature of the proposed thermal models in the warm-up zone is the use of a conditional solid-state environment with combined air characteristics and deformable material in the elastic region. A feature of the used thermal models in the zone of plastic deformation of the tube was the task of the boundary and initial conditions in the form of fixed temperatures. The obtained modeling results were confirmed experimentally on the manufactured machine.