Most of the industrial machines use the belt transmission for the power transfer. These mechanisms often use the round belts with a few millimetres in diameter, which are made of the thermoplastic elastomers, especially the polyurethane. Their production process requires the bonding step, which is often performed by the butt welding, using the hot plate. To design the automatic welding machine in a proper way, the authors analyzed this process. One of the most important parameter which describes the hot plate welding is plasticized distance. Knowledge about its value is necessary to predict the length reduction of the belt during welding and will be used during the quality of the joint rating. To obtain value of this parameter the temperature distribution calculations are needed. The paper shows the results of the analytical calculations of the temperature distribution and their comparison with analyses performed by the FEM implements. Calculations were performed for the thermoplastic elastomer during the heating phase in the hot plate welding process.

The on-going rapid development of industry encourages development of new production technologies and designing of machines that use inventive mechanical engineering solutions, a big demand for parts of such machines being a natural consequence. Polymeric power transmission belts are a good example of that. This paper proposes an improvement in the process of production of such belting. Their production includes cutting to length and splicing of elastic round belts to obtain endless belts of the specified length. This is the key phase of the whole production process. A number of splicing methods are available using different physical phenomena. One of them is butt welding technique. In this process heat is applied on the material through an additional heating element called the heat platen. The effect depends on several factors, including preparation of the work pieces. Due to its characteristics the process is often carried out by hand. The need for automated manufacturing was created by important factors associated with manufacturing on an industrial scale: cost, time and quality. The proposed butt welding machine, complete with a control system is an answer to this need. The practical benefits include improved repeatability of splices, time savings and less work load for the operator.

Most of the industrial machines use round-shaped drive belts for power transfer. These drive belts are often a few millimeters in diameter, and made of thermoplastic elastomer, especially polyurethane. Their production process requires the bonding step, which is often performed by hot plate butt welding. The authors have undertaken an effort to design an automatic welding machine, which calls for an analysis of the hot plate welding process consisting in describing the dependency between the technological parameters (temperature, pressure force, time) and the quality of the joint. To analyze this process in a proper way, it is necessary to describe the physical phenomena in the material during temperature and force impacts. In this case the research of thermomechanical properties of the belts is needed. The paper shows results of some preliminary research of the thermomechanical properties of the polyurethane. This research allows to predict the material reaction to increased temperature and force during hot plate welding.

The paper presents experimental investigations of the compaction process of loose material in the form of sawdust. These were compacted in the sleeve-punch assembly adapted for installation on a strength testing machine. Sawdust was compacted with a force suitable to obtain the desired compressive stress in the sample cross-section. The effect of the composition of the compacted sample was investigated by adding pine sawdust to 50% of the total sample's weight. The experimental compaction process was simulated by building its numerical model using the Drucker-Prager-Cap model. Obtained results of experimental tests carried out on a strength testing machine allowed to establish a numerical model of the sawdust compaction process in the Abaqus program and to assess the possibility of using the Drucker-Prager-Cap model for numerical simulation of compaction process of loose materials in the form of sawdust.

In the processing of waste materials, attention must be given to the efficient use of energy. The pelletization of dry ice is a good example of such processes. A literature review shows that in the pelletizers available on the market, the force applied in the process is excessive. As a result, the efficiency of the utilization of inputs, including electricity and carbon dioxide, is at a very low level. This article presents the results of experimental research on the effect of the degree of dry ice compression on the value of the Poisson ratio. The first part of this article presents the research methodology and a description of the test stand, developed specifically for this research, bearing in mind the unique properties of carbon dioxide in the solid state. The results presented show the behavior of dry ice during compression in a rectangular chamber for different final densities of the finished product. As a result, it is possible to determine the values of the Poisson ratio as a function of density, using for this purpose four mathematical models. The findings of this research may be useful for research work focused on the further development of this process, such as by using the Drucker–Prager/Cap numerical model to optimize the geometric parameters of the parts and components of the main unit of the machine used in the extrusion process of dry ice.

This article presents the results of a numerical experimental study on the simulation of the dry ice compaction process. The first part of the article presents a description of the material used, material models and the methodology of experimental research. In the second part, numerical and experimental study results are presented. For the purpose of comparison, a parametric method based on the residual sum of squares was used. The application of the indicated method fills the gap in the available literature as the authors are not aware of any existing data from previous studies on the method of comparing the results of numerical tests in terms of the obtained results and the change of the value of the tested parameter as a function of another variable. The results of this study can be useful in research work aimed at further development of the process of extrusion and compaction of dry ice using Drucker-Prager/Cap and modified Cam-Clay material models for instance for optimization of geometric parameters of parts and components of the main assembly of the machine used in the process of dry ice extrusion.