In modern mechanical engineering, a method of single-operation extraction of cylindrical parts from a metal grid with a square mesh is known, which, in particular, has found application for the manufacture of microphone casings. Further improvement of the technology of extracting parts from a metal mesh in the direction of increasing the relative height of the stamped part is associated with the use of a multi-operation method of extraction. The study of this process will allow to significantly reduce the limit coefficient of extraction and thereby significantly increase the relative height of the part. Therefore, the work aimed at improving the technology of manufacturing parts from a metal mesh due to the use of a multi-operation method of extraction is an urgent scientific and practical task. The purpose of the study is to improve the technology of manufacturing cylindrical parts from a metal mesh by using a multi-operation method of drawing. The result of the work is the study of physical limitations that determine the limiting coefficient of multi-operational extraction of cylindrical parts from a metal mesh. The phenomenon of elasticity of the mesh wires was revealed, as a result of which the side wall of the part acquires a curved, close to conical shape. The physical similarity between the process of deformation of a single wire of a metal mesh during multi-operation drawing and the process of bending a flat workpiece is shown, which allows determining the technological effort of each drawing operation using formulas for calculating the bending force. In addition, two forms of instability of the process of multi-operational drawing of cylindrical parts from a metal grid with a square mesh were revealed, and a new method of drawing was proposed, which creates such stamping conditions, in which asymmetric deformation of the part (irreparable defect) is not observed, and separate additional means for cutting the edge of the stamped parts are not used.

The most common technology for the manufacture of aluminum parts and blanks is casting in a chill mold. To determine ways to improve casting technology, it is necessary to analyze the possibility of changing the parameters that affect the reduction of production costs (reduction of energy consumption, material consumption, increase productivity) and improve the quality of casting. The thermal regime of the metal form determines the productivity of the process, the duration of curing of the casting, its quality, durability of the chill mold. The analysis of the work of the chill mold for the manufacture of castings Pump Housing showed that when the forms are filled, the most heated new portions of metal meet on their way to the central core. That is, when pouring the mold, the central core is heated the most, especially in the lower part. This circumstance hinders the process of directed curing and can lead to shrinkage defects. In addition, the higher the temperature of the mold, the slower the casting will crystallize and the worse its structure and mechanical properties will be. Based on the analysis of structures and methods of cooling molds, the method of controlled cooling of the central core by air is substantiated. A new design of the core has been developed, which provides adjustable air cooling of the chill mold by connecting the central core through a valve to the pneumatic system of the shop. 3D-models of details and assembly drawings of the central core of a new design are developed. A computer study of the air flow in the core channels in SolidWorks Flow Simulation was performed. The results of parametric modeling of air flow in the channels of the Central core showed the maximum air flow rate during cooling 0.371 kg / s, the heat content of air when cooled 25081 J / s. Evaluation of the cooling efficiency of the developed chill mold design showed that when using air cooling of the central core with cooling air at its maximum consumption, 41% of heat is removed. Thus, the developed design of the cooled central core allows to increase the productivity of the casting process, improve the quality of casting by improving the structure and mechanical properties of the casting, as well as increase the life of the chill mold. But the obtained research results are of a recommendatory nature and require practical verification in the production environment. In addition, the simulation did not take into account the change in core temperature due to its heat exchange with the melt. Given all this, there is a need for further study of the effect of regulated air cooling on the thermal regime of the chill mold.

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The stressed and deformed state of the metal and the dimensions of the center of deformation during pressing depend significantly on the design of the tool and, in particular, on the shape of the matrix funnel. However, there is still no single point of view on the influence of the geometry of the deformation center on the energy forces of the metal pressing process. Based on the analysis of the field of slip lines of the steady-state stage of pressing through a symmetric single-point matrix, it is proposed to use the profile of the matrix funnel made along the slip line separating the elastic and plastic zones. The following types of matrix funnel profiles were investigated using computer simulation of direct extrusion of lead samples with a drawing value 81 at a speed of 1 mm/s: cycloid concave; convex; the second convex, which is built on the logarithmic dependence; conical and concave, which is built along a sliding line that separates the elastic zones from the plastic in the pressing process. The results of theoretical studies, computer simulations of the direct pressing process using the Deform 2D/3D software package, and experimental experiments have shown that optimal energy-power conditions are achieved by pressing through a matrix that has a profile made along the slip line. The results of the experimental study of the kinetics of the flow of the discrete medium showed that the shape of the matrix funnel influences the size of the deformation center and the distribution of the resulting deformation in the molding. From the analysis of deformation of the granules, it is determined that the concave funnel, built along the slip line, is characterized by a curvature of the axisymmetric particles in the direction of deformation. These curvatures decrease as the granules move to the axis of symmetry of the matrix. It is noted that for a convex funnel, the length of the deformation center is greatest; for a conical metal flow is close to the radial in the direction of the truncated cones.