MODELING OF THE PRESSING PROCESS OF TROLLEYBUS CONTACT INSERTS FROM GRAPHITE-PLASTIC COMPOSITIONS

Abstract

The work investigates the process of pressing a trolleybus contact insert from a graphite-plastic powder composition using three-dimensional numerical modeling by the finite element method. The object of the study is the basic design of a mass-produced contact insert used in current collection systems of electric transport.

Most current research on current collection systems for electric vehicles focuses on the analysis of wear of contact inserts during operation, as well as on how operating conditions and material composition affect the durability of the contact pair “insert–wire”. On the other hand, the problems associated with the formation of structural heterogeneity of contact inserts at the manufacturing stage remain insufficiently studied. In particular, the influence of the geometry of the main structure on the movement process remains unexplored. This limits the possibilities of consciously improving the design of inserts and optimizing their manufacturing technology. In this regard, it is important to study the process of movement of the main structure of the trolleybus contact insert, which is used in serial production. For this, it is necessary to use modern methods of numerical analysis. Such a method not only allows to explain the reasons for the structural heterogeneity of the material, but also creates a basis for further improvements in the design of the insert, taking into account operational and technological conditions.

Numerical experiments were performed using the open software package Code_Aster, which allows taking into account nonlinear material behavior, large deformations and contact interaction with friction. The main attention was paid to the analysis of the distribution of the relative density of the material, the flow velocity fields of the graphite-plastic composition and the nature of the change in the pressing force throughout the entire compaction cycle. It was shown that the geometry of the basic design of the insert causes the formation of zones of reduced density, local areas of material circulation and a sharp increase in force at the final stage of pressing. The results obtained can be used as a scientific justification for further constructive modification of the contact insert in order to increase its operational durability.