Purpose. The solution of the problem for determining a specified vertical displacement of supports in a rotating unit, taking into account the yielding in the crosscut of the supporting node, as well as the peculiarities of the structural design.Methods. When performing the work, the approaches based on the elasticity theory principles are used, taking into account the variable transverse crosscut of the unit and the different high-altitude positions of supports. To determine the general expressions describing the axis position of the studied multisupport structure, the Cauchy' function method was used. Findings.A system of solvable algebraic equations has been obtained that enables to perform calculations for a beam-type cylindrical structure on rigid and elastic supports. The expressions are presented for determining the value of vertical displacement of the supports, taking into account the operational characteristics of a unit, in particular the presence of the influence of neighboring supports and the value of existing loads. The cases have been studied of implementing the adjusting displacements, using the obtained equation system with the complete unloading of the supporting nodes, as well as with the use of the technical diagnostics data -the determined values of the total displacements of the supports. Expressions have been obtained for calculating the desired adjustment parameters. An algorithm is proposed for performing the computing operations.Originality. The method of adjustment of the specified position of supports in a rotating unit has been further developed, which is carried out through determining the elastic components, rigid displacements, complete displacement in the supporting node, as well as the results of technical diagnostics.Practical implications. The calculations have been made taking into account the yielding of the supports in the range of maximum and minimum values. It is shown that the value of certain supports displacement, which should be taken into account as a result of their yielding, can reach the extremum standard values. The presence of previous displacements of the supports predetermines a significant acting forces redistribution in the rotating furnace body and is determined by their direction. The value of adjusting displacements has been determined, which should be performed to obtain a rectilinear axis of rotation. It has been revealed that it is appropriate to implement a parallel displacement of the projected axis of rotation for reducing the adjustment parameters in the supporting nodes.

No abstract

No abstract

At present, the use of power hydraulic cylinders is an integral part of most industrial equipment. They provide translational and horizontal movements, replacement of goods, fixation, etc. These devices are necessary elements of the equipment where application of the corresponding level of effort is applied. Often hydraulic cylinders are created specialized to perform certain types of work. It should be noted that part of the elements of the power cylinder in the manufacture is combined with welding. Such integral connections provide rigidity of installation, tightness of a design, fatigue strength at multicycle loadings. Difficult operating conditions, significant workloads, the presence of various external factors often leads to the destruction of individual elements of the cylinder. At the same time, the cost of repairing equipment that involves replacement with new power devices is quite high. This causes the implementation of repair and restoration work carried out at specialized enterprises. However, in the case of repairs, there are often a number of problems that require prompt resolution in the production environment. These should include the provision of basic materials with similar physical and chemical properties, the establishment of welding modes, the selection of the necessary welding materials, the use of appropriate techniques for conducting the arc process, etc. Therefore the repaired welded design of the case of the power hydraulic cylinder needs additional studying for weldability of separate elements among themselves, formation of a zone of thermodeformation influence. In general, the repaired hydraulic cylinder should meet the installation operating requirements depending on the purpose. The design of the considered hydraulic cylinder of the press installation is rather technological from the point of view of maintenance of automation of welding process. It contains long welds of a simple ring configuration. At the same time, the significant linear dimensions and the presence of a cylindrical surface cause some complexity in the implementation of processes. The construction material of the power hydraulic cylinder is low-carbon low-alloy steels. The analysis of technological weldability indicates a tendency to crack due to the thermal cycle of welding. The simulation of welds of the power hydraulic cylinder is performed in the work. The number of rollers was taken into account when obtaining butt welds. A comparative analysis of different electrode materials with different doping systems is done. The most applicable welding materials by chemical composition and properties of the weld metal are determined. According to the literature data and the results of comparative analysis, the optimal range of cooling rate of the main material of the hydraulic cylinder was established. The properties and structure of the zone of thermal influence of the butt welds of the power hydraulic cylinder have been studied. The magnitude of deformations and stresses caused by the thermal cycle of welding of the shell structure of the hydraulic cylinder liner is investigated. The admissible parameters of the zone of plastic deformations during butt welding are determined.

No abstract