Search Results (60)

To enhance the performance of the combined high-pressure grinding roller (HPGR) and tower mill (TM) process for −1 mm particle size, this study addresses the key technical challenges of insufficient material quantity (<100 kg) and complex experimental procedures in HPGR closed-circuit crushing tests by proposing a novel circulating load prediction method based on the principle of mass balance and first-order crushing kinetics. Using a side-flanged HPGR WGM 6020 installation, systematic −1 mm HPGR closed-circuit crushing tests were conducted on seven different ore samples under three specific pressing forces, with detailed characterization of the dynamic variations in product size distribution, specific energy consumption, and circulating load during each cycle. The results demonstrate that within the specific pressing force range of 3.5 N/mm² to 4.5 N/mm² when the crushing process reaches equilibrium, the circulating load stabilizes between 100% and 200%, while the specific energy consumption is maintained within 1–2.5 kWh/t. Notably, at the specific pressing force of 4.5 N/mm², both the circulating load and specific energy consumption rapidly achieve stable states, with ore characteristics showing no significant influence on the number of cycles. To validate the model accuracy, additional samples were tested for comparative analysis, revealing that the deviations between the model-predicted −1 mm product content and circulating load and the experimental results were less than ±5%, confirming the reliability of the proposed method. Full article

Changes in soil properties under mechanical stress significantly influence the emergence and growth of crops, with different crops responding differently to these changes. To explore the impact of different soil compaction states on crop growth, field experiments were conducted in 2022 and 2023 in sandy loam soil in Manitoba, Canada. The crops (canola and soybean) were planted under three compaction levels created by a seeder’s press roller: no press roller (P0), one pass of the press roller (P1), and two passes of the press roller (P2). Soil mechanical properties and plant growth were measured for each treatment. The results indicated that soil shear strength increased significantly with each level of compaction from P0 to P1 and from P1 to P2, while soil surface resistance remained largely unaffected. Interestingly, soybean and canola responded differently to soil compaction. Soybeans showed no significant changes in emergence speed or final plant population across the three treatments. Conversely, canola exhibited over a 50% increase in emergence speed and more than a 100% increase in final plant population with either one (P1) or two passes (P2) of the press roller, compared to the no press roller (P0) treatment. These findings provide valuable guidance for agricultural producers and engineers in adjusting the down pressure of seeder press wheels when planting different crops. Full article

In this study, the authors investigated the briquetting of hydroxyapatite and fluorapatite rock material and evaluated the properties of briquettes prepared in a roller press. This was conducted 10 years after the manufacturing process took place. These rocks are a primary source of the mineral phosphorus, for which demand is high, particularly in agriculture. The proper handling of the material in the industry is required due to its high environmental impact. In order to correctly identify the subject of this study, the authors analyzed its composition using energy-dispersive X-ray spectroscopy, scanning electron microscopy and polarized light microscopy. Afterwards, the authors analyzed the properties of the saddle-shaped briquettes, including their surface roughness (Ra, Rq, Rt), surface Leeb hardness distribution, porosity and density. The briquettes exhibited relatively large Ra values (mean 9.67 µm). The highest hardness was registered at the specimen center (61 HV5), whereas the lowest was at the edge (25 HV5). A high density of 2.51 g/cm³ was achieved in the process. It was possible to obtain saddle-shaped briquettes with reproductible properties, high density (porosity of 21%) and durability without using a binder additive. The study demonstrated that roller press briquetting can be successfully utilized as a method for compacting phosphate-bearing materials for the purpose of storage transportation and further processing. Full article

Defibering equipment is employed in the production of scrimber for the purpose of wood veneer rolling, cutting, and directional fiber separation. However, the current defibering equipment exhibits a notable degree of automation deficiency, relying more on manual operation and empirical methods for process control, which impedes the stability of the defibering equipment and the defibering quality. This study presented an in-depth finite element analysis of the roller-pressing process for veneer defibering equipment, and a prediction method incorporating numerical simulation and ensemble learning was proposed through data collection and feature selection. The objective is to integrate this method into the intelligent decision-making system of the equipment, with the aim of improving the productivity of the equipment and effectively stabilizing the product quality. The simulation process and the analysis of the results in ABAQUS 2020 revealed that the roller gap and roller velocity of the defibering equipment, as well as the geometrical parameters of the veneer, have a significant influence on the defibering effect. Combining these factors, 702 simulation experiments were devised and executed, and a database was constructed based on the model-building parameters and simulation outcomes. The strain and stress observed in the simulation results served to represent the veneer force and veneer deformation. The CatBoost algorithm was used to establish prediction models for the key parameters of the defibering effect, and the Bayesian Optimization and 5-fold cross-validation techniques enabled the strain and stress prediction models to achieve coefficients of determination of 0.98 and 0.97 for the training and test datasets, respectively. Shapley Additive Explanation was used to provide insight into the contribution of each feature, thereby guiding the selection of feature parameters and simplifying the model. The results show that the scheme can effectively determine the core process parameters of the defibering equipment and then provide a practical control strategy for intelligent online control. Full article

This research aims to develop a comprehensive mathematical model to analyze the energy usage of essential equipment in the hot stamping production line (HSPL) and identify opportunities for improving energy efficiency. This involves refining existing models and parameters related to energy consumption in hot stamping to ensure precise energy usage monitoring throughout the HSPL. The main focus is on accurately calculating and validating the energy consumption efficiency of equipment within a product’s production cycle on the roller hearth furnace’s HSPL. The model has proven to be highly accurate in predicting energy consumption for various equipment. The average energy consumption of the HSPL in the case study is calculated as 0.597 kwh/kg, and the actual measurement is 0.625 kwh/kg. However, it revealed significant deviation in the cooling system, primarily due to the incorrect water pump head parameters utilization. As per the model’s calculations, most energy consumption is attributed to the furnace (77.51%), followed by the press (10.92%), chillers (6.86%), cooling systems (2.76%), and robots (1.95%). Actual measurements and model calculations highlight mismatches between equipment power ratings and actual demand, resulting in average operating power significantly lower than the rated power. In line with efforts to promote low-carbon manufacturing, practical approaches are being explored to conserve energy and enhance overall process efficiency by refining process parameters, reducing quenching duration, improving SPM on the production line, and adjusting load matching. Full article

In an age of heightened environmental awareness and the pressing need for net-zero emissions, concerns over rising energy consumption in cement production, responsible for 5–8% of global CO₂ emissions, have intensified. This paper proposes a novel pioneering framework that integrates Shannon’s entropy and Multi-Criteria Decision Making (MCDM) methods to steer the cement industry towards sustainability and net-zero emissions. Utilizing Shannon’s entropy, the research impartially determines the significance of multiple criteria, reducing biases in decision-making for energy efficiency in cement production. Four MCDM methods (TOPSIS, VIKOR, ELECTRE, WSM) are applied to rank energy efficiency alternatives, providing a nuanced analysis of options for the cement industry. The study integrates sensitivity analysis to evaluate the robustness of MCDM methods under varying conditions, assessing the impact of changes in criteria weights on the ranking of energy efficiency alternatives and showcasing the adaptability of the proposed framework. Examining six diverse scenarios reveals the framework’s adaptability and the versatility of the Horizontal Roller Mill (HRM), with the Vertical Roller Mill (VRM) emerging as a cost-effective emission reduction alternative. This interdisciplinary approach, integrating information theory, decision science, and environmental engineering, extends beyond industry relevance, providing valuable insights aligned with global sustainability goals. Harmonizing economic viability with ecological responsibility, this report offers an instructive guide, propelling the cement industry toward a more sustainable future. Full article

The phenolic profile and antioxidant activity of whole grape juices from Vitis labrusca and Brazilian hybrids in two training systems were analyzed. Genotypes of V. labrusca (‘Bordô’ and ‘Isabel’) and Brazilian hybrids (‘IAC 138-22 Máximo’ and ‘BRS Violeta’) were grafted onto the rootstock ‘IAC 766 Campinas’ (106-8 ‘Mgt’ × Vitis caribaea) and trained on low and high trellis. After harvest, the grapes were destemmed and the berries macerated in a roller crusher. Following hot extraction without pressurization of the pomace and gentle pressing of the blend (skins, must, and seeds), the juices were bottled in amber glass bottles and pasteurized. The physicochemical and colorimetric parameters of the juices, as well as the levels of flavonoids, phenolic compounds, total monomeric anthocyanins, antioxidant activity, and polyphenolic profile, were evaluated. The juices were also subjected to sensory analysis (CAAE: 65549817.7.0000.5411). There was broad variation in all assessed characteristics. The results obtained demonstrate that the training system and grape genotype used in juice production are highly related to the presence of sugars, acidity, and bioactive compounds. Juices made from ‘Bordô’, ‘IAC 138-22 Máximo’ and ‘BRS Violeta’ grapes stood out from ‘Isabel’ juices, the main grape variety used in Brazilian juice and wine production. All juices contain bioactive compounds in considerable concentrations, indicating beverages with high antioxidant activity and, consequently, high biological potential, with the use of high trellis in vine cultivation potentially increasing concentrations. Full article

Diatomite deposits in Poland are located in the Podkarpackie Voivodeship, and the only active deposit is in Jawornik Ruski. Therefore, it is a unique material. Improved rock processing methods are constantly in demand. In the research presented here, we have used research methods such as X-ray diffraction (XRD), scanning electron microscope (SEM), particle shape analysis, and appropriate sets of crushing machines. Diatomite comminution tests were carried out on test stands in different crushers (jaw crusher, hammer crusher, high-pressure roller press, ball mill) using different elementary crushing force actions: crushing, abrasion, and impact, occurring separately or in combination. The machines were tested with selected variable parameters to obtain products with a wide range of grain sizes ranging from 0 to 10 mm. The ball mill (yield 87%, system C3) and the hammer crusher with HPGR (high-pressure grinding roller) (yield 79%, system D2 + D3) have the greatest impact on diatom shell release and accumulation in the finest 0–5 μm and 5–10 μm fractions. For commercial purposes, it is important to obtain very fine fractions while keeping the shells undisturbed. Full article

Short carbon fiber-reinforced polymer composites are widely used in polymer extrusion additive manufacturing (AM), including large-area additive manufacturing (LAAM), due to their enhanced mechanical properties as compared to neat polymers. However, the mechanical properties of these composites depend on microstructural characteristics, including fibers and micro-voids, which are determined during processing. In this work, the correlation between fibers and micro-voids within the microstructure of LAAM polymer composites throughout various processing stages of short carbon fiber-reinforced acrylonitrile butadiene styrene (SCF/ABS) is investigated. The processing stages considered here include the incoming pellets, a single freely extruded strand, a single regularly deposited bead, and a single regularly deposited bead pressed by a mechanical roller. A high-resolution X-ray micro-computed tomography (µCT) system is employed to characterize the microstructural features in terms of the fibers (volume fraction, fiber orientation tensor) and micro-voids (volume fraction, sphericity) in the SCF/ABS samples. The results indicate that micro-voids exist within the microstructure of the SCF/ABS composite in all four stages considered here and that the micro-void volume fraction and micro-void sphericity vary among the test samples. Moreover, the results show a considerable variation in fiber orientation and fiber volume fraction within the microstructure throughout all the stages considered; however, all the samples show the highest alignment in the extrusion/print direction. Furthermore, a correlation is identified between the fiber orientation and the micro-void volume fraction within samples from all four stages considered here. This finding suggests that fibers tend to align more in the extrusion/print direction in regions with less micro-void content. Full article

In the heat insulation winding molding process of solid rocket motors, the pressure applied by the press roller directly affects the quality of the winding molding. Insufficient pressure can result in poor bonding quality and may cause defects. This paper aims to provide an optimal design of the press roller to improve the winding molding quality of the heat insulation. The effect of the cylindrical press roller on the pressure distribution was analyzed using the elastic foundation model and a finite element (FE) model, which was assessed by Hertz theory. Subsequently, the press roller was optimized to an elliptical concave design. The effect of the radius of the elliptical concave press roller on the pressure distribution was analyzed. A comparison of the effect of the elliptical concave press roller and the cylindrical press roller on the pressure distribution was conducted using the FE model. The results show pressure uniformity is significantly improved when the elliptical concave press roller is employed on the mandrel with the smallest radius. Additionally, the elliptical concave press roller increases the pressure at the edge of the tape, which reduces the risk of lifted edges and, thereby, improves the winding molding quality of the heat insulation. Full article

Advances in high-pressure grinding roll (HGPR) technology since its first commercial application in the cement industry include new roll wear protection techniques and new confinement systems. The latter contribute to reductions in the edge effects in an attempt to reach a more homogenous product size along the rolls. Additional advances in this technology have been made in recent years, while modeling and simulation tools are also reaching maturity and can now be used to subject such novel developments to detailed scrutiny. This work applies a hybrid approach combining advanced simulations using the discrete element method, the particle replacement model and multibody dynamics to a phenomenological population balance model to critically assess two recent advances in HPGR technology: spring-loaded cheek plates and the offset roller press. Force and torque controllers, included in the EDEM 2022.1 software, were used to describe the responses of the geometries in contact with the granular material processed. Simulations showed that while the former successfully reduced the lateral bypass of the material by as much as 65% when cheek plates became severely worn, the latter demonstrated lower throughput and higher potential wear but an ability to generate a finer product than the traditional design. Full article

As an emerging grinding equipment, roller presses are widely used in Cement industry. The current problem with roller press is that the rolls surface is prone to wear and needs to be replaced regularly. This greatly reduces the service life of the roller press and affects the development of the roller press. Therefore, how to reduce the wear on the surface of the roller press and increase the service life of the roller press is an urgent problem that needs to be solved for the current roller press. Current research mainly focuses on the mechanism research of roller press wear and the optimization of rolls surface structure. In this paper, the extrusion force between the stud-lining and the material is calculated by analyzing the stress of the studded rolls under actual working conditions and the compression and rebound characteristics of material layer. The failure modes of studded rolls are mainly divided into two parts. On the one hand, it is fatigue cracking of the roller shaft and stud-lining. On the other hand, it is cracking at the contact between the stud-lining and the stud, and the fracture of the stud. Because the failure modes of the studded rolls are divided into two parts, the studded rolls are divided into two parts for simulation by using ANSYS 18.0. Firstly, the static analysis is carried out on the roller shaft and the stud-lining, and the distribution cloud diagram of the stress and contact pressure of the roller shaft and the stud-lining is obtained, and the stress concentration area is optimized. After optimization, the contact pressure between the roller shaft and the stud-lining is reduced by about 50%. The maximum equivalent stress of the roller shaft and stud-lining has also been reduced. Secondly, a static analysis was conducted on the stud-lining and studs. Since the stud-lining of the studded rolls are composed of stud holes arranged in a certain order. Therefore, stress concentration is prone to occur around the stud hole. The simulation experiment was carried out by changing the optimization schemes such as the assembly method of the stud and the stud-lining, the distance between the studs, and the length of the stud. To reduce the stress concentration of stud and stud-lining. After optimizing the model of the stud and stud-lining, the maximum equivalent stress of the stud-lining and stud decreased by about 10% and 25% respectively. Through the optimized design of roller shafts, stud-lining and studs. The service life of the studded rolls can be effectively improved and the production cost can be reduced. This can provide a reference for the design of the studded rolls. Full article

The knowledge of the operating conditions in rolling bearings in technical applications offers many advantages, for example, to ensure a safe operation and to save resources and costs with the help of condition monitoring and predictive maintenance procedures. In many cases, it is difficult to implement sensors to measure the operating conditions of the rolling bearing, for reasons such as inaccessibility of the mounting position or non-compliance with installation space neutrality, which influences the sensor on the measuring point. Printed sensors using a digital deposition process, which can be used in very narrow design spaces, offer advantages in this respect. So far, these sensors have not been established in rolling bearings, so there is potential for technical application. This paper discusses the fundamental advantages and disadvantages as well as the challenges of the application, and it demonstrates the feasibility under isolated boundary conditions by applying a printed strain gauge sensor to the outer ring of a cylindrical roller bearing NU210 in an experimental setup to measure the strain under load. In this setup, the outer ring is deformed by 2 mm under an increasing radial load using a hydraulic press, and the strain is measured. Both a commercial reference sensor and a FE-simulation are used to validate the measurement. The results show that an implementation using printed sensors as a strain gauge works successfully. The resulting challenges, such as measuring strain gradients and printing on curved surfaces, are finally evaluated, and an outlook for further work is given. Full article

To address the issues of the existing dry granulation process, which mostly relies on manual adjustments based on empirical experience and lacks the analysis of theoretical data, a simplified model of tablet pressing based on a modified Drucker–Prager Cap (DPC) material constitutive model was proposed to simulate and analyze the forming process of tablets, and study the impacts of the feeding speed, roller speed, friction coefficient and roller clearance on the density distribution of the pressed tablets via ABAQUS. The results show that the roller speed significantly impacts the density of tablets, and a lower roller speed and a higher friction coefficient are beneficial to the formation of tablets. As the roller clearance decreases, the average density at the clearance increases, and the unevenness of the lateral density distribution of the tablets increases, showing a distribution trend of larger density at the center and smaller density on both sides. Full article

In this study, brewer’s spent grains (BSG)-raw matrix was technologically and functionally improved by adding natural active ingredient carriers (crushed wheat, rapeseed, and pumpkin seed press cake) and using planetary roller extrusion and used as feed additive for pigs. Feeding trials were run for 189 days using 60 pigs with an age of 28 days. Pigs were grouped in a control group (fed with organic basic feed) and two experimental groups (fed with BSG 1 or BSG 2 in addition to organic basic feed). The 20 animals per group gained similar weight in the control group (306 g day⁻¹ and 725 g day⁻¹) and in the group fed with BSG 1 (282 g day⁻¹ and 627 g day⁻¹) or BSG 2 (250 g day⁻¹ 598 g day⁻¹) in addition during rearing and fattening phases, respectively. Carcass evaluation revealed that meat quality did not differ between control and experimental groups. The BSG-based feed formulations tested seem to not result in negative effects on weight gain nor on meat quality. Animals were generally of good health and marketable quality, and thus the outcomes of this study are expected to contribute to an improved utilization strategy of brewer’s spent grains from breweries. Full article