Vol 30, No 1 (2024)

The features of multi-connected production systems and their management problems are considered. A model of multi-connected production systems is proposed as a set of processes in the production cycle, taking into account material, information flows and disturbances from the internal and external environment. The state of a multi-connected production system is assessed by technological, technical-economic, organizational indicators and the investment effectiveness. An approach to management based on the concept of lean production is proposed, the goal of management is formulated and the management task is set as a search for rational control actions. The structure of the control system and functional subsystems are considered.

This article discusses the models and methods underlying the functioning of the intelligent information-measuring and control system of a drum drying unit. They allow real-time minimization of losses in the quality of the dried material and the productivity of the drying process. A mathematical formulation of the problem of controlling the drying process with minimization of a given functionality and the structure of a drum drying installation as a control object are presented. Many possible control situations are described, linguistic variables are formulated, membership functions of terms of linguistic variables are determined, and a base of fuzzy control rules is formed. Examples of calculating the control action minimizing the loss functional, and the intelligent information-measuring and control system of the drum drying unit that implements it are shown.

An approach to automated selection of the type of submersible drum and the shape of a conductive anode in an installation for galvanic coating of parts in bulk, based on the use of the theory of constructing expert systems, is considered. The problem of optimal selection of the type of submersible drum and the shape of the conductive anode is posed and solved. The issues of constructing an information and logical model for supporting decision-making in their selection are considered, which allows, depending on the given shape and size of the processed parts in bulk form, to find the optimal option for the type of submersible drum and the shape of the conductive anode in the installation. To prepare design documentation for a multifunctional installation for galvanic coating of parts in bulk, digital parametric models of possible types of drums and conductive anodes were developed in the SolidWorks system. A software package that implements the solution to the problem has been developed and tested during the galvanizing process of small parts (studs, bushings, nuts).

The process of assessing efficiency during the design and operation of an information system – a complex automated system – is considered. Options for decomposition of information system efficiency indicators and assessments of the effectiveness of the functioning of its elements are presented. In this case, the control system is assumed to be centralized, single-link. Standard indicators of the management process (operability, continuity, stability and secrecy) are considered. The functioning of the system is assessed based on the phase trajectories of the reference values.

Stochastic modeling of the process of formation of rarefied flows of bulk components at the stage of rotational mixing on the platform of cyber-physical systems was carried out. The use of the energy method for a stochastic description of the technological operation of mixing solid dispersed media in the working volume of a mixer-compactor with rotary elements made it possible to obtain analytical relationships between the indicators of the process under study and its main design and operating parameters, as well as the physical and mechanical characteristics of the working materials.

The results of the development of porous plate-like regenerative materials based on potassium superoxide and calcium peroxide are presented. Peroxide compounds are synthesized in vacuum from a liquid-phase mixture of potassium peroxide and calcium peroxide diperoxyhydrates with heat supplied in the form of infrared radiation and are fixed in the pores and on the fibers of the fiberglass matrix. The introduction of calcium peroxide into the composition of the regenerative material improves the chemisorption properties of the resulting material due to the formation of refractory and less hydrophilic calcium compounds than potassium compounds. This enables to maintain the spatial structure and porosity of the plates during operation. Plates of regenerative material are proposed for use in smoke protection hoods.

Literary data on waste recycling are summarized to obtain a compact copper deposit by electrolysis. A mathematical model for the electrical extraction of copper from nitrate and sulfate electrolytes with a decrease in the operating current density as the electrolyte is depleted has been proposed and experimentally confirmed. The developed electrolysis models were tested in the processes of technological processing of concentrated copper-containing waste to obtain a precipitate of compact high-purity copper.

The refined problem of calculating a rational allowance using the Python programming environment has been solved, the algorithm and program for calculating the rational allowance and determining the required number of transitions to achieve the parameters of surface roughness and dimensional accuracy specified in the design documentation have been modernized. A description is given of the developed algorithm for automatically determining operations and assigning tolerances, the implementation of which in the Python programming environment allows you to perform calculations for all turning operations and select their quantity, which significantly simplifies the work of technologists at the stage of technological preparation of machine-building production.

The results of an experimental verification of analytical expressions for determining the axial force arising in a fastener when tightening it with torque using a certified torque wrench are analyzed. Analytical calculations of the force in fasteners are presented using known expressions for bolts М12´1.75, М16´6 and М20´2.5 with the construction of a graphical dependence of the force in the bolt rod on the tightening torque and experimental studies of the same dependence, on experimental model of a flange connection using strain gauges glued to the bolt rod. The experimental dependence of the force on the tightening torque and the expression for its determination are given. From the analysis comparing analytical and experimental expressions it follows that the actual load on the bolt is less than its analytical value, which must be taken into account in the calculations.