Investigations into the quality of overhead contact wire installation
Summary
In order to ensure the quality of current collection between current collectors and contact wire according to the Technical Standard of Interoperability (TSI) and the European Standard EN 50119 for the chosen catenary system (its design will depend on maximum running speeds and electrical performance requirements), the contact wire must have a defined and constant nominal tension force in its final position. This will provide an appropriately uniform elasticity of the catenary system and minimise the residual vertical ‘ripple of the contact wire’ post-installation.
In addition, the inherent ‘residual ripple’ which remains after the ‘manufacture and installation of contact wires’ (as defined by EN 50149) must be avoided or reduced by proper installation processes as much as possible.
Plasser & Theurer have developed a catenary renewal machine (FUM) which ensures time-efficient installation of contact wires under pre-selected constant nominal tension force.
The present paper uses examples to explore the residual ripple to be expected in ÖBB's shaped contact wire 120mm² ( CuAg 0.10 alloy) after its installation by an FUM machine.
In addition to experimental studies identifying accurate wire parameters, the possible causes of ripple effects in contact wires are presented. The subsequent mechanical modelling and numerical simulation focus on vertical deformations which remain after unreeling and installing the contact wire wound around the drum in an elasto-plastic manner.
In conclusion, and based on special experiments, the long-term and short-term creep behaviour of the installed contact wire is discussed.