The article describes the main principles of the movement around the circumference of the cranes circular steps. It is proved that the defining characteristics of the organization of the movement of the crane on the circle are the geometric parameters of the mutual reversal of the running wheels of the crane, not the observance of the reversal determines the transverse slippage of wheels of the crane, and the shape of the wheels depends only on the elastic longitudinal slide. The result of slides and slippage is firing the head of the rail with one hand and the loss of stability when moving the crane. Stability stability ensures the achievement of the precision targeting of the gripping device. These parameters are the main performance characteristics that should be valued in absolute terms should be minimal.

Keywords: nuclear power station, crane circular steps, suspension bridge crane, suspension wheel, cylindrical wheel, bevel wheel, the mutual reversal of wheels

the article presents the study in the control of the geometric parameters of wheels of cranes circular steps. The options considered to determine the radii of the wheels by indirect methods, of which the most effective are those based on the construction of the measuring triangle at the open part of the forming. As the final results and proposals noted the following: both control provide almost ravnovesnye results definitions of the geometric parameters of the wheels; more universal is the way to control the radius of the wheel, using calipers and this method is recommended when addressing these and similar problems.

Keywords: Running wheels, geometrical parameters of wheels, crane of circular action, wheel radius, wheel cone corner

In article the analysis of ways of increase and criteria for evaluation of stability of the welding arc category is carried out. The most perspective way of increase of stability of the arc category, can be carried out due to pulse, high-frequency impact on a welding contour. The experimental data obtained at research of the combined power supply system of the arc category of a direct current at parallel connection to the main welding power supply of the additional generator of impulses are given. Influence of a pulse component from the additional generator with a frequency of 40 kHz, on stability of burning of the arc category is considered at manual arc welding by the covered electrodes. As criteria for evaluation of stability of burning of the arc category have been accepted such as, the explosive length of an arch with which there is it's natural break and coefficient of stability. The conducted pilot studies and positive results of skilled approbation of the developed power supply system of the arc category allow to recommend it for application at installation of responsible metal designs.

Keywords: Stability, the welding arc category, welding by the covered electrodes, pulse impact on a welding contour, explosive length of an arch, stability coefficient, the electromagnetic field, the generator of impulses