Industrial mixers are equipment used to mechanically combine different types of materials in order to obtain homogeneous mixtures. In concrete industry production, mixers play a crucial role by facilitating the efficient and consistent blending of various constituents to create high-quality concrete. Because the mixers in the concrete industry work in conditions characterized by abrasive and erosive loadings, the authors of this paper tried to establish a dependence between the quality of the material from which the mixing elements are made and their wear resistance. Three types of cast irons alloyed with chromium, specific to the construction of mixing blades, were used in this research. The working environment was a mixture of crushed mineral aggregates corresponding to the granulometric class 4–8 mm. The tests were carried out on an experimental stand designed and built by the authors of this paper. The stand reproduces on a scale of 1:2 a drum made up of a double-axis horizontal mixer. The stand had the possibility to change the value of the attack angle of the mixing blades, corresponding to the following values: 30, 45, and 60 degrees. The results of the tests established the dependence between the type of material and the wear rate of the blades as well as the influence exerted by the angle of attack on the wear of the mixing blades. It was shown that when the inclination angle of the blade relative to the shaft axis increases, the cumulative mass loss decreases, with values between 43% and 55.83%, as a function of the quality of blade material.

In this article, the authors present the results obtained within a complex experimental program that focuses on determining the tribological characteristics of the friction materials used in transmission belts, which are critical active components in manipulators within the pharmaceutical industry. The elements of transmission belts, having the role of ensuring the movement of cardboard packaging—used when packing the foils with medicine capsules—and stopping them during the insertion of the foils, were studied. This repetitive cycle—travel-braking—leads to the wearing of the friction material on the active surface of the belt. The experiments were carried out in a dry environment (air) by testing different types of friction materials (original belt, 3D printed TPU 60A, and TPU 95A). While the study is limited to these three materials, the results highlight the significant influence of material type and infill percentage on the coefficient of friction (COF) and wear resistance. TPU 60A achieved the highest COF at 100% infill, indicating a superior grip but experienced substantial wear, under the same conditions. Conversely, TPU 95A demonstrated a lower COF, suggesting reduced grip, but exhibited exceptional wear resistance. The aim of the research is to provide a preliminary investigation into the materials’ wear resistance and braking effectiveness. The experiments utilized appropriate samples to replicate real operational conditions, particularly focusing on the nature of contact between the moving belt and the packaging.

This study has the main objective the flow modelling using CFD through active parts waterjet cutting machine, model YCWJ-380-1520. More precisely, the study of flow through the cutting head and estimate the erosion wear caused by abrasion of these parts. The active parts of cutting head are the body of head, high pressure nozzle with jewel and mixing tube made from wolfram carbide. On all these components has previously done measurement in order to create the geometrical model. The most wearing subjected parts water-jet machine are the water nozzle and mixing tube where the erosion wear is accelerated by the high velocity. In the first part of this study is presented the water flow model without regarding the abrasive inlet geometry, using Ansys FLOTRAN CFD. Has been considered three dimensions of water nozzle along with three dimensions of mixing tube in order to evaluate velocity variation at mixing tube outlet and how geometry influences outlet velocity. The second part of this paper is made using CFD software Ansys Fluent regarding a tridimensional geometry and a multiphasic flow. In the framework of flow model is established the abrasive particles velocity, difference of pressure inside tube, contour of streamlines, shear stress on the tube wall in order to accomplish the erosion rate during the process flow. It can be noticed that there are two main streamlines: first at the outlet of water nozzle and second from the inlet of abrasive material. Particles velocity is higher at the contact with water stream and lower at the end of cutting head because the difference of diameters between jewel and mixing tube. The maximum erosion rate is recorded where the shear stress are high values, that means to the interior wall of water nozzle and inlet of mixing tube. Pressure becomes high to the jewel of water nozzle and decreases in value toward at outlet of cutting head.

In this paper, the authors present the results obtained within a complex experimental program that focuses on determining the tribological characteristics of the active part (tungsten carbide tooth tip) of the cutter teeth of asphalt milling equipment. The experiments are performedunderdifferent testing conditions (in a dry environment and in water) to highlight the need to use water, when milling the asphalt coating, with the purpose to reduce the wear of milling teeth. The experimental results show that water contributes to the substantial reduction of wear rate (more than eight times) on the active area of the tooth. The proposed test method—testing with the Baroid tribometer—is intended to evaluate the tribological characteristics of the materials using parallelepiped-shaped samples. The authors of the work performed the tests on samples that represent the teeth of the milling cutter having the real shape (so not on samples). The obtained results demonstrate that the test method can be used with good results on real parts.

Abrasion wear is a significant concern for cutting tools, particularly when milling asphalt concrete due to the presence of hard mineral aggregate particles. The pressure exerted on the cutting tool by the chipped material and the resulting cutting forces directly influence tool wear. To estimate the cutting forces in asphalt milling, the authors propose using either laboratory experiments or cost-effective Discrete Element Method (DEM) modeling—by simulating the real conditions—as direct measurement under real conditions is challenging. This article presents results from an original experimental program aimed at determining the cutting forces during asphalt pavement milling. A specialized stand equipped with a moving plate and recording devices was designed to vary milling depth, rotational speed, and advance speed. The experimental results for horizontal force values were compared with numerical results from DEM modeling. It was found that both increasing the milling depth and the advance speed lead to higher cutting forces. Generally, DEM modeling trends align with experimental results, although DEM values are generally higher. The statistical analysis allowed identification of the milling depth as the most significant parameter influencing cutting force and the optimal combination of milling parameters to achieve minimum horizontal force acting on cutting tooth, namely, 15 mm milling depth and 190 mm/min advanced speed.