The use of selective induction heating of molding surfaces allows for better filling of molding cavities and has a positive effect on the properties of molded products. This is particularly important in the production of parts that include flexible hinges, which are thin plastic layers connecting two or more parts of the product. By using hinges, it is possible to expand the use of injection molding products and their capabilities. They are widely used in the production of parts for the electrical engineering industry and for packaging Fast Moving Consumer Goods (FMCG). The use of hinges also entails specific reductions in wall thickness. Increases in the shear rate can be expected, which can lead to the degradation of polymers and deterioration of mechanical properties of materials. This paper investigates injection molded flexible hinge parts manufactured with selective induction heating to improve their properties. To verify the efficiency of reduction of material degradation due to high shear rates, open/close tests of elastic hinges were performed. The linear relation between the number of cycles the hinges can withstand, mold temperature and injection time was identified, where mold temperature was the more significant factor.

In order to increase the quality of the products manufactured by injection molding, RTC technology can be used to achieve higher mold temperatures. As a result, the path of the injected melt can be extended, allowing the production of parts with more complex shapes and greater length. Induction heating allows heating only selected forming surfaces of the mold which increases the speed and efficiency of the process. This paper presents the concept of a detachable inductor integrated with sliders to enable the application of this technology in an injection mold with sliders, along with the theoretical model used to perform the tests. First, the effect of the magnetic concentrator shape on the process was analyzed. This was followed by a simulation study of the influence of process parameters: heating time, frequency, and electric current. An extensive analysis of the test results of the temperature distribution on the insert allowed for the selection of parameter sets that would enable obtaining the desired surface temperature without a major increase in process time. The results of simulation studies confirm the possible applications and present the range of parameters for obtaining the optimal process.

Lubrication is a critical aspect of the metal forming process and it is strongly influenced by the surface texture of the tool-forming surfaces. This study is focused on determining the effect of surface finish and heat treatment on wettability involving commonly used lubrication agents. Three different finishing states are evaluated (as-ground, as-polished and as-nitrided). Surface topography was measured using a focus variation microscope. Parametric evaluation was carried out according to ISO 25178, including fractal methods. The functional relations between the finish state and wettability, lubricating agent and wettability, selected surface parameters and wettability, as well as between finish state and selected surface parameters, were designated. The results showed that surface finishing treatments, particularly nitriding, influenced both surface roughness and wettability, with varying effects observed across different lubricants and droplet sizes. The findings provide valuable insights into the optimization of lubrication strategies for metal forming processes, highlighting the importance of tailored surface treatments for enhanced tool performance and longevity.

Nowadays, crucial parts of modern Building Automation and Control Systems (BACS) are active control and monitoring functions. Many of research have been conducted to investigate the support of location-based services (LBS) for individuals in the BACS. Since microlocation technology could be used to enable reliable and precise indoor positioning and navigation, an indoor positioning system (IPS) has been proposed as an attractive way for activity recognition and support LBS. In this paper an investigation of using microlocation with Bluetooth Low Energy technology to develop an active BACS has been presented. Case study of such system is described and the results from verification of reliability and accuracy of localization process have been discussed.

The article presents an energy analysis of a real suction-pressure unit of a high-efficiency radial piston pump. This pump can be used in small hydropower plants, where, together with a variable displacement hydraulic motor, it would form a hydrostatic transmission. The main advantage of this solution is the possibility of a stepless, automatic change of gear ratio during its operation, which allows an increase of the efficiency of power generation in a hydropower plant. Mathematical models of friction and resistance of flow through self-acting and geometrical deformations of chambers and piston under stress field are presented. In addition, mass, volume, and energy balance calculations were computed for the ideal unit and pressure losses were determined. Derived indicator diagrams for each chamber of the ideal suction-pressure unit served to analyze the technical work of occurring processes. The paper also presents the formulation of total efficiency of the unit. Lastly, the experimental procedure is presented, according to which it is possible to register the most important parameters of the proposed model.