In the first article, on the basis of the analysis of a number of studies, some of the provisions set forth by the author in the issue of NAMI works No. 57 of 1963 are checked. , and relating to elements of technical theory. The main attention is paid to the initial task - the evaluation of the rolling process of the wheel with an elastic tire on a solid support surface. The purpose of the work is to select the most reliable ideas about the methods of quantitative evaluation of the rolling process by disclosing a number of significant contradictions that still occur in the technical theory of rolling of the elastic wheel. The work is designed for engineering and scientific workers of industries related to wheeled railless transport . The second article describes the equipment for measuring by semiconductor sensors the rate of flow in the rotating wheel hydrotransformer and the installation for calibration of sensors, as well as the results of this calibration. The third article is devoted to clarifying the nature ofthe interaction between the crossbar and the longeron at the torsion ofthe car frame. Methods of the theory of elasticity revealed the distribution of stresses and displacements in the longzheron from the bimo-ment of the crossbar and showed the coincidences and differences of these stresses and displacements from the results of the calculation according to the theory of thin-walled rods .. Determined the distribution and relative magnitude of local stresses in the area of the frame node. The fourth article discusses modern methods for identifying the actual austenitic grains of hardened steel. Recommendations on the method of detection of steel grains after induction quenching. The results of the study of the kinetic growth of austenitic grain in “hereditarily” fine-grained and coarse-grained steels with an increase in the temperature of induction heating.