{"title":"Obtaining the Selected Surface Roughness by Means of Mathematical Model Based Parameter Optimization in Abrasive Waterjet Cutting","authors":"A. Perec, F. Pude, Michael Kaufeld, K. Wegener","doi":"10.5545/SV-JME.2017.4463","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4463","url":null,"abstract":"The study on the effect of abrasive water jet machining process parameters on micro alloyed steel surface roughness was described. Taguchi method to predict machining parameters of due to minimum surface roughness was used. The influence of pressure, abrasive flow rate and traverse speed on the Rz and Rmax roughness parameters were presented. The optimum combination of processing parameters was established. Verified parameters were tested and the achieved results were compared to predicted values. This method allows limiting the amount of research needed to achieve the desired test results, thereby reducing the time as well as the cost required to carry them out. The Taguchi signal/noise (S/N) ratio enables the assessment of the relevance of the impact of various parameters on the process, which is still not well enough understood.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"31 1","pages":"606-613"},"PeriodicalIF":1.7,"publicationDate":"2017-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82795469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Zaremba, P. Heitzmann, L. Overmeyer, Lennart Hillerns, T. Hassel
{"title":"Automatable Splicing Method for Steel Cord Conveyor Belts – Evaluation of Water Jetting as a Preparation Process","authors":"D. Zaremba, P. Heitzmann, L. Overmeyer, Lennart Hillerns, T. Hassel","doi":"10.5545/SV-JME.2017.4363","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4363","url":null,"abstract":"The increased demand of mineral resources leads to worldwide application of incessantly longer conveying systems. The length between axes can amount to 15 km and more. Owing to manageable dimensions and weight, appropriate conveyor belts are produced in segments of up to 300 m. Final assembly takes place at the conveyor system, where the multitude of segments is connected to a long conveyor belt. An important point in assembly preparation is the stripping of the steel cords, which is mainly carried out manually using rudimentary techniques. The optimization potential is high, since the adoption of automatable and application-oriented preparation methods can minimize the conveyor downtime and improve the joint quality. \u0000In this study, the application of the pure water jet is investigated, since this selective stripping method offers a lot of potential for automation and the creation of rough surfaces. The objective was to determine if an efficient, homogenous and selective removal of the rubber is possible without damaging the zinc coating of the steel cords. Following a parameter study, the generated kerf geometries and surfaces were investigated. The stripped steel cords and zinc coatings were analyzed through the preparation of micrographs. Concluding, an evaluation about the qualification of water jetting as an automatable method for joint and repair preparation is made.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"43 1","pages":"590-596"},"PeriodicalIF":1.7,"publicationDate":"2017-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79002883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Klich, Dagmar Klichová, Vladimír Foldyna, P. Hlaváček, J. Foldyna
{"title":"Influence of Variously Modified Surface of Aluminium Alloy on the Effect of Pulsating Water Jet","authors":"J. Klich, Dagmar Klichová, Vladimír Foldyna, P. Hlaváček, J. Foldyna","doi":"10.5545/SV-JME.2017.4356","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4356","url":null,"abstract":"Erosion effects of a pulsating water jet impinging the surface of aluminium alloy samples pre-treated by various techniques (rough and fine milling, planing and rolling) were studied. The influence of the initial surface topography on the final topography of the sample exposed to the pulsating water jet was investigated. Based on roughness parameter Ra erosion of surface layers was analysed and discussed in relation to the traversing speed of the jet. It was found that initial surface pre-treatment have a significant impact on the final topography of the surface affected subsequently by pulsating water jet. Surfaces, whose properties are significantly affected by the action of some machining processes (i.e. milling) show much greater resistance to pulsating water jet than unpaved surfaces (i.e. rolling) and surfaces have smaller roughness. While milled (rough or fine) or planed surface roughness has approximately the same increase of Ra parameter, only rolled surfaces are up to 150 times rougher after pulsating water jet treatment. This is due to the small hardening of the surface layers and reduced durability against pulsating water jet in comparison with others investigated techniques. The highest roughness was achieved on all pre-treated surfaces at the lowest speeds, because the pulsating water jet affects the surface for a longer time.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"38 1","pages":"577-582"},"PeriodicalIF":1.7,"publicationDate":"2017-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74780146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optimization of Hybrid Manufacturing for Surface Quality, Material Consumption and Productivity Improvement","authors":"D. Grguraš, D. Kramar","doi":"10.5545/SV-JME.2017.4396","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4396","url":null,"abstract":"This paper presents hybrid manufacturing process of 3D printing and milling. Fused deposition modeling (FDM) has been applied to improve product manufacturing performance, afterwards, milling was used to improve outer surface roughness. Today’s FDM systems rely on the use of standard nozzle size with a diameter of D1 = 0.4 mm. To achieve shorter production times a bigger nozzle size (diameter D2 = 1.1 mm) has been used in this research. Optimization of technological parameters of hybrid manufacturing was carried out according to the minimal time of production, a minimal final surface roughness and minimal usage of material. In addition, these results were compared with optimal results obtained with the standard nozzle size. Significantly shorter production time, without affecting surface quality, was achieved when using bigger nozzle size.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"6 1","pages":"567-576"},"PeriodicalIF":1.7,"publicationDate":"2017-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80562454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vladimír Foldyna, J. Foldyna, Dagmar Klichová, J. Klich, P. Hlaváček, L. Bodnárová, T. Jarolím, K. M. Kutláková
{"title":"Effects of Continuous and Pulsating Water Jet on CNT/Concrete Composite","authors":"Vladimír Foldyna, J. Foldyna, Dagmar Klichová, J. Klich, P. Hlaváček, L. Bodnárová, T. Jarolím, K. M. Kutláková","doi":"10.5545/SV-JME.2017.4357","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4357","url":null,"abstract":"This paper presents first results of the study of the resistance of carbon nanotube concrete composite (CNT/concrete composite) to the action of continuous and pulsating water jets. The experiments oriented at the determination of erosion effects of pulsating and continuous water jets impinging the surface of reference (concrete) and CNT/concrete composite samples were performed. Tested samples were characterized by X-ray powder diffraction and scanning electron microscope. Samples were exposed to pulsating and continuous water jets at various operating parameters. Erosion effects of pulsating and continuous jets were evaluated in terms of material removal rate. The possible influence of addition of CNTs to the concrete on its resistance to the action of continuous and pulsating water jets is discussed in the paper. The experiments proved that CNT/concrete composite exhibits higher resistance than reference concrete to the action of both pulsating and continuous water jet under the given testing conditions.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"191 1","pages":"583-589"},"PeriodicalIF":1.7,"publicationDate":"2017-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76937751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Valentinčič, Matej Peroša, Marko Jerman, I. Sabotin, A. Lebar
{"title":"Low Cost Printer for DLP Stereolithography","authors":"J. Valentinčič, Matej Peroša, Marko Jerman, I. Sabotin, A. Lebar","doi":"10.5545/SV-JME.2017.4591","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4591","url":null,"abstract":"A general research direction of stereolithography based on digital light processing (DLP) is to reduce the production time and to increase manufacturing accuracy. Compared to fused deposition modelling (FDM) machines, machines for DLP stereolithography are expensive andthus not available to a broad range of users as it is the case with FDM 3D printers. Comparing technologies, DLP stereolithography offers quicker and more accurate production. In this paper, performances of a low cost DLP stereolithographic printer is presented. Three main challenges are treated: an uneven illumination of commercial DLP projectors, a direction of illumination and a selection of optimal 3D printing parameters. Uneven illumination of DLP projector results in smaller usable working area and poor printing quality. The problem is solved by implementing an appropriate software mask, thus the product quality is not influenced by its position on a working table. The direction of illumination has a key role in DLP stereolithography. It is shown that constrained surface (illumination through a transparent bottom of the vat) gives better 3D printing accuracy compared to free surface (illumination of the photopolymer surface) stereolithography. To further improve the product quality, the optimal process parameters are determined. Using the Taguchi based surface response methodology optimal process parameters are defined and by using them, the deviation of the actual dimensions from the specified dimensions is less than 80 μm.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"2 1","pages":"559-566"},"PeriodicalIF":1.7,"publicationDate":"2017-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90927371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Integrative CAE-Driven Design Process in the Embodiment Design Phase of L7e Vehicle Structures","authors":"Roman Pawel Jedrzejczyk, M. Alb, T. Jost","doi":"10.5545/SV-JME.2017.4489","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4489","url":null,"abstract":"In the past decade, the mechanical engineering industry has searched for a design methodology that could systematically unify the support of computer-aided engineering (CAE) tools for the design process. More recently, some propositions have been put forward for the CAE-driven design process (CDDP), but the efficiency of these design processes is questionable. We have proposed improvements and new arrangements that result in the integrative CDDP (ICDDP), which makes CDDP more reliable, efficient and predictive. The ICDDP redefines the role of CAE tools and positions the optimization technology as a fundamental driving force behind the whole design process. Consequently, the ICDDP orders design phases as: (1) conceptual design, (2) design crystallization and (3) design sophistication, which steer the design process sequentially. The accurately established linkages between the sequential design steps enhance the smooth recurrence of the ICDDP for new product executions. In addition, this work demonstrates the application of the conceptual design phase to design a new L7e (eQuad) vehicle structure. This phase of the ICDDP illustrates the specific steering methodology for the topology optimization of a new eQuad structure as well as the geometric solution derivation step that reveals the transformation of bionic shapes into rough manufacturable geometry. Additionally, the numerical verification of the simple geometric model is presented for the load cases given. Our results exemplify the fact that the ICDDP allows engineers to design new innovative and lightweight structures.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"16 1","pages":"3-16"},"PeriodicalIF":1.7,"publicationDate":"2017-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78405347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Herrejón-Escutia, G. Solorio‐Diaz, H. Vergara-Hernández, E. López-Martínez, G. M. Chávez-Campos, O. Vázquez–Gómez
{"title":"Electric-Thermo-Mechanical Analysis of Joule Heating in Dilatometric Specimens","authors":"M. Herrejón-Escutia, G. Solorio‐Diaz, H. Vergara-Hernández, E. López-Martínez, G. M. Chávez-Campos, O. Vázquez–Gómez","doi":"10.5545/SV-JME.2017.4320","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4320","url":null,"abstract":"A mathematical model of Joule heating was developed for an AISI 304 stainless steel in a hollow cylinder dilatometric specimen. The model was developed by means of creating a balance of energy by coupling the generation term due to the Joule heating and the thermal expansion of the specimen. A Newtonian heating system was assumed for a volume element, and it was resolved by means of the finite differences method, generating its own computer code in the Scilab free-license software. The model considers the thermophysical and electrical properties of steel, depending on the temperature. Thermal interactions at the boundary and the linear thermal expansion coefficient were determined by solving the inverse heat conduction problem (IHCP) using the thermal profile and thermal expansion measured experimentally by means of a direct heating device. The model was validated by comparing the thermal response and experimental thermal expansion with simulated responses for different heating rates.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"13 1","pages":"537-547"},"PeriodicalIF":1.7,"publicationDate":"2017-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83149300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Neural Network-Based High-Accuracy Motion Control of a Class of Torque-Controlled Motor Servo Systems with Input Saturation","authors":"Lei Liu, Jianpei Hu, Yuangang Wang, Zhiwei Xie","doi":"10.5545/SV-JME.2016.4282","DOIUrl":"https://doi.org/10.5545/SV-JME.2016.4282","url":null,"abstract":"The torque-controlled motor servo system is widely used in many industrial applications. However, input saturation often occurs due to the limitation of the actuator output ability, which may worsen the system control performance. In this paper, in order to inhibit the impact of input saturation on the system, a single-hidden-layer neural network based observer is designed to estimate the value of input saturation, which could later be compensated in the proposed controller. In addition, an adaptive law is introduced to estimate the unknown parameters, and a nonlinear robust term is designed to overcome the time-varying disturbances and other compensation errors. The Lyapunov theorem is used to prove the stability of the proposed controller with the neural network-based observer. Extensive comparative experimental results are obtained to verify the high-performance of the proposed control strategy.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"71 1","pages":"519-528"},"PeriodicalIF":1.7,"publicationDate":"2017-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86308198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of a Force Model Adapted for the Precise Turning of Various Metallic Materials","authors":"R. Horváth, J. Lukács","doi":"10.5545/SV-JME.2017.4430","DOIUrl":"https://doi.org/10.5545/SV-JME.2017.4430","url":null,"abstract":"The knowledge of cutting forces is critical. They might affect the load of the machine and, in the case of fine turning, the deformation of thin and slim workpieces. The generated forces depend not only on material properties (hardness, tensile strength) and on cutting parameters, but also on the tool edge geometry, that strongly determines the geometry of the chip (thickness and width). This article deals with the application of a force model adapted for precise turning technology. Three different types of materials widely used in mass production were taken into consideration (C45 and KO36 steel types and AS12 die-cast aluminium alloy). The components of cutting force were measured in three directions (Fc , Ff , Fp ) and the specific cutting forces were calculated. The main values of specific cutting forces were introduced for precision turning (k1, 0.1); using this, a new force model was constructed based on the theoretical parameters of the non-deformed chip cross-section (heq is equivalent chip thickness and leff effective length of the edge of the tool) in case of all three examined materials. Investigations revealed that the influence of leff on specific cutting force components is not negligible; however, it has the least effect on kc and is the most influential in case of kp. The errors of the constructed new force models follow Gaussian distribution with low values of standard deviation. Thereby, the models can be applied to estimate cutting force components during the technological process planning procedure with adequate accuracy.","PeriodicalId":49472,"journal":{"name":"Strojniski Vestnik-Journal of Mechanical Engineering","volume":"12 1","pages":"489-500"},"PeriodicalIF":1.7,"publicationDate":"2017-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73743310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}