International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The trend of using micro-parts in modern industry puts new tasks for contemporary production technologies. If these parts are made of difficult-to-machine materials, machining problems become more complicated. On the other hand, the requirements go towards manageable and stable production processes, reduction of the processes number, reduction of the machining cost, using of clean technologies, etc. Use of mechanical solid tools in engineering materials micro-machining, many problems occur, such as: high machined surface roughness of the, tool deflection, intensive tool wear, etc. These problems lead to difficulties in establishing adequate process models, and thus the ability to control of micro-milling process and it’s including in smart processes and smart factory concepts. This paper presents the possibilities of using micro-milling in the difficult-to-process materials machining. The phenomena in micro-cutting are analysed, as well as the output machinability indicators (surface roughness, tool wear, etc.). As a conclusion, guidelines and technological frameworks for the application of micro-milling in practice are given.

Photovoltaic thermal system (PV-T) converts sunlight into electricity and heat simultaneously. The overall efficiency of these systems is higher than the efficiencies of PV panels and solar collectors together. In Albania energy production from photovoltaic systems has been promoted in the recent years. Albania’s Mediterranean climate conditions are very favourable for investment in renewable energy systems. In this study a stand-alone 280 W PV-T panel is considered with respect to thermal analysis of the system. The panel is installed at the terrace of the building University in Tirana, Albania. The aim of this work is to present the temperature profile of the panel, since there is a correlation between efficiency and temperature. In order to analyse the temperature distribution on the panel surface a series of experiments are carried out. Temperature variation vs. time for different water flow rate was performed. The inlet and outlet water temperature profile is drawn in this article.

The study is a review of the scientific and applied content of the research carried out over the years on the topic, both worldwide and by the authors. The research is structured in a way that presents the topic in its active development over the years, which substantially proves its permanent relevance. The development of the researches of the spatial transformation of motions, oriented towards the synthesis and analysis of spatial transmissions with innovative characteristics, at this stage and up to the present moment for Bulgaria are realized exclusively at the Institute of Mechanics at Bulgarian Academy of Sciences (BAS). The content of the researches carried out at the Bulgarian Academy of Sciences clearly determines their market orientation and, therefore, their place of development was in the “Centre of competence MIRACle – Mechatronics, Innovation, Robotics, Automation, Clean Technologies” at the Institute of Mechanics. The above said makes it inexplicable the decision of the former management of the institute, in the face of Prof. Vasil Kavardjikov (Director) and Assoc. Detelina Ignatova (Project Manager), to ignore this topic when designing a project for the creation of the Competence Centre.

The possibilities of using the investment potential of industrial enterprises are investigated. The expediency of formation of investment potential of industrial enterprises is substantiated. The methods and procedure for assessing the effectiveness of the investment potential of the enterprise are analyzed. The organization of the system for managing the efficiency of the investment potential of an industrial enterprise is proposed.

Risk management constitutes currently one of the most important elements of the management of an enterprise, which is crucial to its security and continuous improvement. This is a several-stage process, and its implementation should systematic and principled in character. The article sets out the risk assessment for activities performed in conjunction with individual operations of a manufacturing process, and specifically, the book production process. The risk assessment was preceded by the identification of hazards to technological, transport and control operations, followed by their analysis using an indicator method. Operations have been identified, which are characterized by the highest risk, and preventive and prophylactic actions using various control measures (technical, organizational, legal, individual and collective) have been proposed. Risk assessment for a task is a primary outline for the use and implementation of risk management issues that go beyond the commercial risk assessment in an enterprise.

The article provides an analysis of the excitation conditions and the results of the detuning of parametric resonance in mechanical drive amphibious water-jet machines. The paper substantiates the possibility of solving the problem of reducing the dynamic load on the basis of the synthesis filter low-frequency vibrations.

Prevention of industrial accidents in Europe and creation readiness of the authorities and the community for countering them are aimed not only at major catastrophes, but also at the small ones, which threaten the society, jobs and environment. Regardless of the internationally accepted framework for prevention and counteraction the industrial accidents involving hazardous substances (refers to the Seveso type site/area related accidents), there are fields that have not yet been developed, such as an assessment of the vulnerability of various sectors of economy, their interdependencies and the impact on social life. Considering these challenges, the main objective of the current article is to bring to the attention of stakeholders an integrated package of advanced developments, both in terms of Seveso type site/area related accidents, caused by reason of technological failures (technological mistakes) or are due to targeted man-made activities (terrorism).

Digital environment progress towards real and virtual realities mixing is reasonably producing new understandings for ICT progress expectations. In todays’ mobile web world, augmented realities are practically integrating ‘Internet of Things’ (IoT) mobile concept and 3D visualization technologies into a new evolving smart world. This changes our everyday life concepts, adding capabilities with innovative functionalities. However, it also is generating multiple challenges from cybersecurity perspective. This paper studies the problem for human-machine interaction, accentuating on the multifaceted understanding of possible threat sources and attack vectors in the new augmented reality research area. In this context, a system model with prognostic analysis is proposed. The necessity of obtained results validation is finally discussed.

This report examined the means of automated design and analysis of technical documentation in CAD environment. Based on the analysis is to develop a methodology for course work in the discipline technical documentation using CAD systems for students of all engineering disciplines. The introduction of CAD products CAD early in training will enhance student motivation for their use – further in the education process in diploma projects.

The polymeric composites on the basis of a thermosetting matrix, chaotically reinforced chemical fibers with a broad band and high level of operating performances have been developed. The optimum geometrical parameters of a fibrous filler, degree of filling of a matrix at a different dispersibility of a filler ensuring high technological effectiveness and degree of strengthening have been defined. The thermodynamic conditions of obtaining strong adhesive connection of a matrix with a filler have been explored during receiving polymeric composites.

Gantry cranes are particularly suited to lifting very heavy objects, especially in shipbuilding industry are used massive objects like ships’ engines to be lifted and moved over the ship. Capacity of the overhead gantry cranes increased proportionally through the needs. In this study dual-trolley heavy duty overhead gantry crane that can carry loads up to 800 tons was designed and analyzed. Stress and displacement values of main beam were calculated by both Finite Element Method and using mechanical formulas. As a result, it has been seen that, F.E.M. is a quite practical method to handle stress analysis problem of gantry cranes.

For handling of partial or continuous goods, belt conveyors are very efficient way. Belt conveyors are used in mining, iron and steel plants, thermal power plants, ore, coal, limestone, sinter transmission, automotive and the other sectors. There are several factors that have to be taken into consideration when a belt conveyor being designed. That means belt conveyor design process requires repetitive strength calculations. But analytical calculations are not capable of determine to entire stresses which occured at whole body. During the design process, time can be saved with the assistance of Finite Element Method. In this study; as a result, it has been seen that, F.E.M is the most practical method which can be utilized during belt conveyor design process.