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In this paper, the particularities of applying parameterization in industrial machines corresponding to the manufacturing area are exposed and analyzed. For its development, the parameterized design of a die cutting machine is proposed as an object of study, which is formulated from the main elements considered of importance in the principle of operation, being necessary to carry out a prior investigation to analyze it and how the parameterization process influences. Parameterization is a quality of the components to adapt flexibly to the needs of the industry or sector, facilitating the redesign and manufacturing process, allowing the desired dimensional update or adjustment to be carried out only to the central component and the others are automatically adapted. Attending to the current needs and trends of the fourth industrial revolution, as well as establishing the benefits of this type of flexible design processes to expand their implementation to different industrial machines such as robot configurations.

In the preparation of the die cutting process, basic adjustments can be made based on the appearance of the creases and emerging material damage. To achieve an accurate optimization, more elaborate analysis methods are needed. The object of the study was to develop a practical and accurate accessory device for a material tester that combines the advantages of laboratory measuring equipment as well as die cutting tools used in industrial applications. The operation of the developed device and the evaluation method were verified with a series of creasing tests with commercial sample materials. Special attention was paid to crease dimensions, level of spring back, folding resistance and forming force optimization. The changes in the crease material thickness increased as a function of forming depth as expected. The same consistency was not found in the comparison of the depth of the creases formed in different directions. Spring back of the material was deduced to be a significant factor for the final dimensions of creases. In addition, it was discovered the creases do not have to be die cut too fiercely, as the desired functionality can be achieved with less force. Obtained results were considered beneficial in the analysis of materials and in the control of the die cutting process.

Creasing and scoring are methods used in the production of carton blanks in package manufacturing. The objective of this paper was to compare the creasing and scoring processes to investigate the effect on the performance in folding and in manufactured packages. A series of converting experiments and measurements were performed to investigate the differences between the processes. The results show differences between the creased and scored samples. The blanks die-cut with flatbed die cutting machine required the lowest folding force, while the packages manufactured with laser scoring had the highest compression strength. The results indicate that all methods are suitable to be used in the manufacturing of carton blanks.

Micro-cutting edges are often used for the die cutting of functional films and paper containers. A hardening process is needed here because the ridgelines of micro-cutting edges require not only we...

Digital twin (DT) is a core technology that enables the integration among physical machines, tools, material handling and warehousing, and real-time manufacturing decisions. In this study, a DT fra...

Метою даного дослідження є попередній розрахунок і моделювання технологічних параметрів процесу висікання картонних розгорток у пневматичній системі засобами автоматизованого проектування SolidWorks. У даний час проектування, модернізація і удосконалення ротаційного обладнання вимагає оригінальних технічних рішень, особливо для виробництва різнопрофільних картонних паковань. Йдеться про якісний технологічний процес висікання в зоні «ніж—контрніж» і взагалі про виконання завершальних робіт. Проблема дослідження стосується ріжучих і обробних виконавчих механізмів. Відповідно використання пневматичних систем може істотно спростити процес висікання. Розроблений на кафедрі модуль для висікання може бути вбудованим у транспортувальну систему. Наприклад, у стрічковий конвеєр. Таке комбінування транспортера і ротаційного модуля для висікання картонних заготовок вимагає додаткових теоретичних і експериментальних досліджень. Equipment for the manufacture of cardboard products is constantly being improved. New sections for die cutting are being designed. As well as devices for carrying out technological processes of die-cutting and cutting down of cardboard products. The tendency to improve the rotational method of trimming and die cutting of sheet materials is increasing. The main problem in the design of die cutting equipment is the quality of the processes performed. The advantages of the rotary die cutting sections include high productivity. Therefore, improving this process is very important. This article deals with the technological process of cutting in the knife-counter—knife zone. The problem of the interaction of cutting actuators is considered. The use of pneumatic systems greatly simplifies the die cutting process. An advantage of the pneumatic die cutting module is that it can be integrated into the transport system. This combination of conveyor and rotary module allows for curved separation of cardboard sweep. The aim of this study is to simulate the technological parameters of the process of cutting cardboard reamers in a pneumatic system. The calculation was carried out by computer aided design. Accordingly, in the working area of die cutting of the pneumatic system, the air pressure changes. Therefore, temperature parameters of air are important parameters. As previous studies have shown, air temperature can affect the performance of the rotary die cutting module. With increasing temperature, the required air flow rate increases to maintain the required working pressure. This is directly related to a decrease in air density with increasing temperature. Improving the geometry of the nozzle of a pneumatic system is an important study. A partial drop in pressure in the working areas of the die cutting can lead to a decrease in the quality of material processing. The basis of the work is research on the influence of air flow and its temperature variables as a characteristic working fluid. Additional studies carried out using the SolidWorks computer-aided design system show the dependence of the air volumetric flow rate on its variable temperature in the working area of the pneumatic rotary die cutting section.

A Blowout Preventer (BOP) serves as a safety valve in the drilling process in the oil and gas industry. It will be closed if an influx of formation fluids occurs and threatens the rig. A Ram BOP is one type of widely used BOP. It is composed of two ram blades, which will move towards each other to shear the drilling pipe and to close the valve. To ensure the shearing process be completed on the rig, lab tests are often run to evaluate the BOP’s capability and the required shearing pressure. The paper presents a new automation CAE (Computer-Aided Engineering) toolkit method recently developed to simulate the Ram BOP pipe shearing process. The toolkit method automates and integrates the process from computer aided design (CAD) to computer aided simulation for the Ram shearing process. It significantly simplifies the modeling effort and facilitates the design optimization process.

Piezoelectric materials have been widely used in modern science and technology due to their electro-mechanical coupling response. Sometimes, because of the stiff and brittle nature of some piezoelectric materials, the piezoelectric devices with defects may face fracture or failure during their service procedures. Therefore, it has become important to investigate the failure behaviors caused by defects, such as cracks and holes. Based on the study of the dynamic anti-plane characteristics for radial crack emanating from a circular cavity in piezoelectric bi-materials, this paper aims to analyzes the dynamic incident anti-plane shearing (SH-wave) in piezoelectric bi-materials, which contains two interfacial cracks, near an eccentric elliptical hole. Green’s function method, the conformal mapping method, the interface conjunction techniques and the crack-deviation techniques are utilized to obtain a series of first kind Fredholm’s equations, based on which the dynamic stress intensity factor (DSIF) at the outer and the inner cracks’ tips are theoretically expressed. Numerical examples were graphically presented to illustrate the effects of the piezoelectric parameter, the effective piezoelectric elastic modulus, the dimensionless incident wave number and geometric parameters on the DSIF at both of the tips. Previous studies are not comprehensive, especially when the center of the hole deviates from the interface. Therefore, the impact of eccentric distance on DSIF is considered in this paper. The solution of this problem provides a more accurate and efficient method for the investigation of dynamic fracture properties of piezoelectric materials and has an important theoretical significance in engineering design.

A large amount of packaging used mainly in the food industry is obtained by technologies that involve the use of machines such as those that cut with flexible die. The durability of the flexible die is a very important aspect and in this regard the purpose of the research was to identify technologies for its development. Thus, the research considered the analysis of the durability of the knives made of 50CrMo4 steel considering hard chrome-plating treatment, as well as laser hardening of the knives. For the analysis of the durability of the tools, two technological parameters were considered, namely the moment of the tightening force, which had values in the range of 50 Nm–110 Nm, and the die cutting speed, which was adjusted to values in the range of 50–60 m/min. For the analysis of the durability of the flexible die, the wear of the tools was taken into account, as well as the maximum length of the die cut material.

To form the required shapes from advanced high strength steels sheets, such as dual-phase (DP) steel, shearing processes are commonly used. In general, although good cut-edge characteristics can be often achieved by setting a small shearing clearance, a scar still remains a major defect on the cut-edge. Therefore, in the present study, the mechanism of scar formation of a DP steel sheet, grade SPFC980Y (JIS) subject to a shearing process was investigated and clarified based on the microstructural evolution, fracture mechanism, and a stress distribution analysis. The microstructural evolution in both tensile test specimens and sheared workpieces were observed to identify the fracture mechanism. The angle between the shear band and the elongated grain flow direction during tensile testing was examined and used to predict the angle of initial fracture and its propagation during the shearing process. With the stress distribution analysis of the shearing zone during the shearing process, the fracture could not propagate into the shearing zone and be directed to the die tip, resulting in the formation of a smooth region again. This feature occurred as a cyclic loop as the punch stroke proceeds and resulted in scar defects in the case of SPFC980Y. However, when the fracture propagation remained in the shearing zone, the fracture was not delayed and fracture was completely generated on the cut-edge in the case of a baseline SPCC steel.

Polytetrafluoroethylene (PTFE) has been studied as a low friction surface coating since its discovery. The high wear-rate of PTFE reduces the usefulness of the polymer for mechanical purposes; however, combining PTFE with polydopamine (PDA) has been shown to greatly reduce the film wear-rate. During rubbing tests involving PDA/PTFE thin films, a tenacious layer of PTFE remains intact after substantial testing even though pure PTFE film layers are destroyed quickly. Understanding the interface mechanics that allow PTFE and PDA to adhere so well during experimental rubbing tests is necessary to improve the wear-rate of PDA/PTFE thin films. In this study, we use density functional theory (DFT) and molecular dynamics (MD) simulations to investigate the adhesive properties and interface deformation mechanisms between PDA and PTFE molecules. Steered molecular dynamics (SMD) is then performed on isolated pairs of PDA and PTFE molecules to investigate different modes of deformation from equilibrium. PDA trimer oligomers were identified as the most adhesive to PTFE and selected to use in a PDA/PTFE thin film, where nano-indentation and scratch tests are performed. Our results indicate that a combination of the unique deformation mechanisms of PDA molecules and the penetration of PTFE molecules into the PDA substrate provide the PTFE/PDA interface with its wear resistance.

Corrugated plate dryer is a extremely vital equipment for steam-water separation in the fields of heat transfer and nuclear engineering. The corrugated plate is also a commonly used steam-water separator in steam generators in nuclear power plants. It is meaningful to study the breakdown characteristics and mechanism of the water film on corrugated plate wall. Water film thickness of steady flow is measured based on plane laser induced fluorescence (PLIF) technique and time series and its fitted equation of water film thickness are obtained, respectively. Besides, fluctuation characteristics of water film are analyzed by probability density function (PDF). Based on the dimensionless approach, the water film breakdown model at the corner of the corrugated plate is established. And the calculation equation of the relative position of the water film breakdown at the corner is deprived. The specific conclusions are as follows. The theoretical equation agrees well with the relative position of the water film breakdown at the corrugated plate corner. The evolution of the surface wave of water film is carried out in time and space. The PDF curve have no significant peak characteristics. Therefore, the spectrum has no characteristic frequency, that is, the water film has multi-frequency characteristics. Gravity of water film can be ignored in the water film model. The thickness sequences for falling film is measured and fitted. The two-dimensional model of water film breakdown at the corner is set up. The equation for the film thickness when the water film is just ruptured is obtained. Relative position of the water film rupture at the corner of the corrugated plate is theoretically related only to the structural parameters of the corrugated plate, the parameters of the gas phase and the liquid phase, and the Reynolds number of the liquid film. However, in the low Reynolds number region, the airflow velocity is extremely large, which causes certain fluctuations and nonlinear characteristics of the water film boundary position. Therefore, the theoretical formula is not particularly good at predicting the relative position of the breakdown in this region. I think that this nonlinear feature has obvious chaotic characteristics. The study of the chaotic characteristics generated by shearing the liquid film by high velocity flow airflow at the corner of the corrugated plate may become a prospect for future research.

The aggregation behavior and the subsequent deposition behavior of wax crystals own undesirable effects on the production and transportation of waxy crude oil. The understanding and prediction of these behaviors are essential to ensure economic and uninterrupted flow of waxy crude oil when the oil temperature decreases below the wax appearance temperature (WAT). In this paper, a novel method of fractal dimensional analysis was introduced to elucidate the aggregation behavior of wax crystals in different shear flow fields. The fractal methodology for characterizing wax crystal aggregation was then developed, and a blanket algorithm was introduced to compute the fractal dimension of the aggregated wax crystals. Considering the flow characteristics of waxy crude oil in a pipeline can be correlated with the shearing stress work, a modified wax deposition model focusing on shearing energy analysis was established. The results indicate that a quantitative interpretation of the wax crystal aggregation behavior can be realized using the fractal methodology. The aggregation behavior of the wax crystals is closely related to the temperature and shearing experienced by the waxy crude oil. The aggregation behavior will be intensified with decreasing temperature and shearing effect, and a wider fractal dimension distribution appears at lower temperatures when the same shear rate range is used. Furthermore, the improved model provides a method for discussing the effects of the operating conditions on wax deposition. The average relative deviation between the improved model prediction results and experimental results from the literature is 3.01–5.32%.

Anisotropic textiles are commonly used in wearable applications to achieve varied bi-axial stress-strain behavior around the body. Auxetic textiles, specifically those that exhibit a negative Poisson’s ratio (v), likewise exhibit intriguing behavior such as volume increase in response to impact or variable air permeability. Active textiles are traditional textile structures that integrate smart materials, such as shape memory alloys, shape memory polymers, or carbon nanotubes, to enable spatial actuation behavior, such as contraction for on-body compression or corrugation for haptic feedback. This research is a first experimental investigation into active auxetic and shearing textile structures. These textile structures leverage the bending- and torsional-deformations of the fibers/filaments within traditional textile structures as well as the shape memory effect of shape memory alloys to achieve novel, spatial performance. Five textile structures were fabricated from shape memory alloy wire deformed into needle lace and weft knit textile structures. All active structures exhibited anisotropic behavior and four of the five structures exhibited auxetic behavior upon free recovery, contracting in both x- and y-axes upon actuation (v = −0.3 to −1.5). One structure exhibited novel shearing behavior, with a mean free angle recovery of 7°. Temperature-controlled biaxial tensile testing was conducted to experimentally investigate actuation behavior and anisotropy of the designed structures. The presented design and performance of these active auxetic, anisotropic, and shearing textiles inspire new capabilities for applications, such as smart wearables, soft robotics, reconfigurable aerospace structures, and medical devices.

Creasing is a method, which is used to produce grooves in fibre-based materials, such as multi-layer paperboard or composite materials such as polymer-coated multi-layer paperboard. These grooves act as folding lines, which guide and control the subsequent folding of the material. The formation of creases is crucial for the functionality of produced blanks in subsequent processes, such as press-forming where the creases have an effect on the formability of materials. The plastic deformation and geometry of creases for polymer-coated and uncoated multi-layer paperboard were investigated using two different creasing processes, flatbed die cutting and a digital creasing and cutting table with a creasing wheel. The presence and dimensions of the creasing grooves were varied to investigate the effect on the formed shapes. A wide area 3D measurement system was used to analyse and measure the dimensions of the formed creases. The results show that that the used process and tool selection has a clear effect on the formed shapes. Based on the results, recommendations for tooling selection are given. Post-print / Final draft

The aerospace propulsion industry has seen strides in the use of the additive manufacturing (AM) technology in the rapid prototyping and geometric design flexibility of aerospace parts, with concurrent efforts on 3D printing turbine engine blades of Inconel 718 material [1] for use in aircraft engines. The tensile, compressive and axial fatigue response of AM Inconel 718, along with associated constitutive modeling of the material response exhibited under these mechanical test conditions have been reported. However, in addition to understanding the axial behavioral response exhibited by this material, assessing the role of cyclic shear stresses, through experimental testing and constitutive modeling can provide preliminary insight into the mechanical behavior of AM Inconel 718 under multiaxial loading conditions. This study has presented a novel approach to constitutively model the experimental cyclic shearing deformation of as-built direct metal laser sintered (DMLS) Inconel 718, manufactured along varying build orientations in the xy, yz and xz planes, compared with wrought annealed Inconel 718. Specimens were subjected to completely reversible torsional fatigue tests at room temperature, under angle of twist control. The experimental cyclic shearing response was modeled through the use of the Chaboche model, from which optimized constants are reported with build orientation; and the specimen deformation, under angle of twist control, was captured through a finite-element simulation model of the cylindrical gauge section of the specimens. Overall this study yields a comprehensive understanding of the experimental and modeled cyclic shearing response of an additively manufactured metal, which is vital to develop these components to be conducive for the multiaxial fatigue conditions to which they are subjected to in the gas turbine industry.

Gas foil thrust bearings have been utilized in high speed lightweight machines for many decades. These bearings are environment-friendly and capable of withstanding extreme conditions. However, there are also some challenges for foil thrust bearings at high speed conditions, such as insufficient heat dissipation and thermal management. The heat generated by viscous shearing continues to raise the temperature inside the gas film and may cause failures. Among all the methods to enhance heat dissipation, a promising passive thermal management method is modifying the top foil’s trailing edge shape. This modification will enhance the air mixing in between the bearing pads. The aim of this study is to identify the optimal design of the top foil trailing edge shape and provide a guideline for future bearing design. A 3-D computational fluid dynamics (CFD) model for a thrust foil bearing was created using ANSYS-CFX software. The trailing edge of the top foil was modified to a chevron shape. A sensitivity study was conducted to investigate the connection between the top foil trailing edge shape and the thermal conditions in the gas film. The maximum temperature inside the air gas film is selected as the output. The design of experiments (DOE) technique was used to generate the sampling points. A surrogate model was generated based on the output data by using the neural network method. The surrogate model was used together with a genetic multi-objective algorithm to minimize the maximal temperature inside the gas film and maximize the load carrying capacity. The optimal design was then compared with the baseline model. Results suggest the optimized trailing edge shape is capable of reducing the temperature inside the gas film. This optimal design approach can be used for improvements of chevron foil thrust bearing design.

The treatment of early age cyclic loading (EAC) on pile-sleeve grouted connections is one of the challenging problems encountered in the design of offshore jacket structures. ISO 19902 appears to be the only offshore structural design code that quantifies the strength de-rating due to EAC. However, the mechanism of EAC considered in the ISO standard is little understood. Main provision is that the strength reduction due to EAC is considered to be linearly proportional to the compressive strength of the grout. This provision is conservatively applicable for medium strength grouts. However, it is over-conservative when modern high-performance grouts are used, and it can be further argued that it actually loses its physical meaning. Thus, a further investigation into the mechanics of the problem is deemed beneficial in order to understand better its underlying mechanism. Using existing experimental evidence and a simple mechanical model, it is shown that the EAC mechanism considered in ISO 19902 triggers the grout matrix failure mechanism of the grouted connections. This behavior is characteristic of segregating grout materials. The benefit of the approach followed is that it links the interpretation of EAC to the grout material properties. The phenomenon is then understood using methods and experimental results that are well established in concrete mechanics. After a comparison with existing experimental evidence on grouted connections and concrete members, it is suggested that the strength drop for the specific shearing mechanism is independent of the uniaxial compressive strength of the grout material.

Currently, the shaped parts combined with straight, concave, and convex portions are increasingly fabricated. To produce the straight portion, the shearing theory is usually applied. As well as, to produce the concave and convex portions, the punching and blanking theories are usually applied. However, with the same die-cutting process parameters, the comparison of cut surface features of straight, concave, and convex portions has not been investigated yet. Therefore, in the present research, the comparison of the cut surface features in various die-cutting processes, including shearing, blanking, and punching processes are investigated. The finite element method (FEM) was used as a tool to investigate these cut surface features. The cut surface features were investigated and clearly identified via the changes of the stress distribution analyses. The results elucidated that with the same die-cutting process parameters, the different cut surface features were obtained. Specifically, the crack formations were easily generated in the case of blanking process, following by the shearing and punching processes, respectively. Therefore, the smooth cut surface was smallest in the case of blanking process, following by the shearing and punching processes, respectively. The laboratory experiments were carried out to verify the accuracy of the FEM simulation results. Based on the cut surface features, the FEM simulation results showed good agreement with the experimental results in terms of the cut surface features. Therefore, to design the die-cutting process parameters to meet the product requirements of complicated shapes, the understanding on these working process parameters being upon the shaped parts is necessarily.

The tool life becomes one of the critical manufacturing issues in the metal forming process of advanced high-strength steel as the material strength continually increasing. In this paper, an evaluation method on trim die chipping damage was developed. This method is based on the measurement of chipped volume, which is achieved from the area measurement on two chipped die surfaces on front and top views, to construct a missing metal triangle, which is further integrated along the die cutting edge line to obtain the loss metal volume. 18 dies made of three different materials (Caldie, AISI D2, and Vanadis 4) and six trim uphill angles were received and measured with the known total trimming cycles (hits). The measurement was achieved with two methods using two combinations of camera view directions. The die materials and trim uphill angle effect on the die performance (chipping resistance) were obtained based on average chipping rate, defined as the loss metal volume per hit. For AISI D2 dies, wide scattering of the chipping rates was seen. And it was identified that the unfavorable carbide/grain orientation relative to the trim die cutting edge line is responsible to the obtained unusual low cycle to failure. Furthermore, a simple in-line real-time die damage monitoring and measurement system is proposed, and the favorable die machining orientation relative to the rolling coordinate is suggested.

En este Trabajo Fin de Grado, se ha pretendido enfocar en los útiles de estampado en frio para la fabricación de componentes, entre otros del sector de la automoción. Veremos que propiedades ha de tener uno los aceros utilizados en la fabricación de componentes, las características físico - mecánicas y la ciencia química que le otorga características específicas. También la teoría que nos explica la manera de ser trabajado, junto a la normativa que se le es de obligatoria aplicación en criterios de calidad. Explicaremos la composición de un troquel, piezas y su funcionamiento, además de un repaso de la calidad del acero que lo compone. Concluyendo con la importancia de su mantenimiento y puesta a punto, crítico para el buen desempeño de dicha herramienta en su trabajo diario de 24 horas por 7 días a la semana. ABSTRACT: In this End of Degree Project, it has been tried to focus on the tools of cold stamping for the manufacture of components, among others of the automotive sector. We will see what properties must have one of the steels used in the manufacture of components, the physical-mechanical characteristics and the chemical science that gives specific characteristics. Also, the theory that explains the way to be worked, together with the regulations that are mandatory application in quality criteria. We will explain the composition of a die, parts and their operation, as well as a review of the quality of the steel that composes it. Concluding with the importance of its maintenance and fine tuning, critical for the good performance of this tool in its daily work of 24 hours for 7 days a week. Grado en Ingeniería Náutica y Transporte Marítimo

The effect of the nozzle top lip thickness on a two-dimensional wall jet was examined experimentally in a wind tunnel using hot-wire anemometry. Lip thicknesses of 0.125b, 0.5b, 1b, and 2b, where b is the jet nozzle height, were considered at a Reynolds number of 30,700 based on the jet nozzle height and jet velocity. Noticeable differences in the flow profiles were observed at the jet outlet, but by 10b downstream these differences became insignificant. Different lip thicknesses resulted in different maximum velocity decay rates. The spread of the wall jet was found to be insensitive to the lip thickness.

Journal bearings of high torque diesel engines are used to cater for high combustion loads which are applied intermittently. A lubrication layer is provided between journal (crankshaft) and bearing to avoid contact between them. The relative velocity between crankshaft and journal bearing results in viscous shear heating among the different layers of lubricating oil. The shear heating reduces the viscosity of the lubricant that ultimately reduces the load carrying ability of the journal bearing. It offers a physical contact and reduces the designed life of crankshaft. In this study the 2-D transient numerical lubrication model is developed by employing the Reynolds equation to calculate the pressure and film thickness profiles as a function of crankshaft speed. The shear heating effects are determined by coupling the energy equation with lubrication model. The finite difference method is used and an appropriate numerical scheme is employed to simulate the conduction and convection based thermal energy transfer in transient and steady state journal bearing lubrication model. The lateral displacement of crankshaft is incorporated in the thermal model to analyze the effect of secondary dynamics of crankshaft. The viscosity and temperature relationship are used to ascertain its variation with temperature. The characteristic of three different viscosity-grade lubricates are incorporated separately in the model to carry out the comprehensive comparative analysis. The results are simulated for particular application where low operating speed and length to width ratio of journal bearing is fixed and analyzed the results for complete 720 degrees of crankshaft in its two revolutions. The results show that the oil with high viscosity produces high hydrodynamic pressures as compared to the oil that have low viscosity. The viscous shearing temperature reduces the hydrodynamic pressures but still the high viscosity lubricating oil have enough pressures to uplift the shaft after incorporating the shear heating effects. This study determines the hydrodynamic pressure, and variation of density, viscosity and thermal-conductivity with temperature for three different lubricating oils. These analyses will facilities towards the selection of appropriate lubricant for high torque low speed diesel engine in order to enhance the life of crankshaft.