Analysis of Mechanical Properties of Gas Pipeline Materials
Vladimír Chmelko, Matúš Margetin
Summary: The mechanical properties of pipes are subject to scrutiny at virtually only the design stage. In most cases, their values are accepted from certificates. The article summarises and compares static tensile tests on the materials of twelve different pipes. Some of these materials were also subjected to dynamic impact tests and cyclic fatigue tests. The results of the tests are mainly compared in two groups: materials used in the transit gas pipelines and materials used in gas distribution systems. Important findings and conclusions largely concern the stability of the materials’ deformation and dynamic (fracture) properties after more than 30 years in operation.
Alternative Fuels and Infrastructure
Summary: The contribution analyses the current hot issue of the development of alternative powertrains and fuels, including the required infrastructure, from the purely technological as well as economic perspectives. The analysed issue entails a mix of the current aspects and trends in transport and energy, and also the technological development and level of the relevant technologies. The subject of the discussion is, therefore, the technology of the conventional engines compared with electric motors, and powertrains fuelled by CNG/LNG, hydrogen and other available alternatives. The author wants to answer the question of which of the available technologies, and under what conditions, can have the ambition to become the fuel of tomorrow and why.