This monography presents the results of research on the operational damage to sectional insulator guides made of hard electrolytic copper Cu-ETP (Electrolytic Tough Pitch Copper). In the first part of the monograph, the authors describe the genesis of electric rail transport. Then, the wear mechanisms of the electric traction contact wires were characterised. This chapter emphasises the influence of the contact surface of electrical wires with the graphite cap of the current collector. The influence of the sliding speed between the graphite overlay and the electric traction cable on its wear was characterised. The influence of the increase in friction velocity on the temperature caused by the friction of the cooperating surfaces and thus on its oxidation, was described. The authors have shown that the wear of the pantograph contact strip materials, as well as the contact wires, is related to the friction products formed on the contact surfaces. In the research part of this monograph, the authors set themselves the goal of presenting and examining the mechanisms that are responsible for damage and destruction of copper guides of sectional insulators. Then, using this knowledge, an attempt was made to increase the tribological properties of the guide's working surface by laser melting with chromium powder. The aim of the research was to produce hardened working surfaces of the guide and to develop technological assumptions for the production of commercially improved guides with extended service life. Laser remelting was performed by feeding the powder with a speed in the range of 0.2÷0.8 mm3/min in a continuous manner to the area of the molten metal pool by dispensing granules using a fluidized bed feeder. CrAl powder was used as the alloying material. Based on the macro-inspection of surface layer remelting, the optimal laser power P = 4kW for the Cu-ETP copper substrate material and the appropriate speed of fusion and remelting the guide were determined. It was found that the optimal speed of the laser beam Vskan=0.05m/min. The powder feed rate was 0.2 mm3/min, 0.4 mm3/min and 0.8 mm3/min In the research part, guide rails that were used on various railway routes were analysed under real conditions, on which the trains ran at a maximum speed of 40 to 120 km/h for periods of 6 to 12 months. Using an Olympus light microscope, the surface microstructure was examined, the surface of the copper guides that is in contact with the graphite plate of the current collector and the cross-section of the guide in the place of its damage. Chemical composition analysis in the EDS micro-areas was performed using a Zeiss Supra 53 scanning electron microscope (SEM), while qualitative X-ray phase analysis was performed using a Panalytical X'Pert diffractometer. In the microstructure of the damaged parts of the sectional insulator guides, cracks and deformations of the surface layer were observed, characteristic of the phenomenon of friction caused by the current collector. The effect of a very intense oxidation process and the action of the electric arc were also observed, which, according to the authors, is the most destructive factor for the condition of the guides. Hardness was measured on a Zwick/ZHR hardness tester using the Rockwell method. The indenter load was 590 N and the indenter diameter was 1/16 inch. The abrasion resistance test was performed on a tribometer with a counter-sample made of ZrO2 in the shape of a ball with a diameter of 6 mm and a load of 10 N. The analysis of the geometry of surface was based on data acquired with measurement of selected fragments of guides, executed on a MicroProf laser profile measurement gauge from FRT company. Thermal wear, arc erosion, and abrasive wear are the dominant wear mechanisms occurring in the process of sliding friction with the accompanying electric current flow, along with material transfer. The last chapter of the monograph presents a model of the relationship between the duration of the process (friction of the current collector and the catenary), the flowing current, the speed of the train, and the pressure of the pantograph, and the temperature generated on the contact surface of the traction system and the current collector. Neural networks were used for this purpose. The simulation results allow us to estimate the influence of selected factors on the temperature generated at the point of contact between the contact wire and the current collector. On the basis of the simulations presented, it is possible to predict the parameters impact of the considered on the increase in temperature and its possible impact on the degradation of the contact wire material.