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1 – 10 of 42Yu-Ting L.V., Yong Li, De-Xing Yang, Zhenhua Bai, Jinlong Li and Rui Wang
Continuous annealing (CA) units usually lack a physical shapemeter; consequently, real-time display and closed-loop control of the strip shape are impossible to achieve.
Abstract
Purpose
Continuous annealing (CA) units usually lack a physical shapemeter; consequently, real-time display and closed-loop control of the strip shape are impossible to achieve.
Design/methodology/approach
A shape model for the CA process is established in this study. Specifically, a virtual shapemeter and closed-loop control system based on the advanced parameter acquisition system and information transmission of CA units are developed in C++ programming language. This system realises real-time dynamic shape display, closed-loop control and shape prediction by collecting raw data of steel coils and parameters during CA.
Findings
Field test results show that the shape predicted by the virtual shapemeter coincides with the measured shape by over 90 per cent, which fully meets the precision requirement of industrial applications.
Originality/value
Moreover, shape quality is effectively improved without increasing hardware investments.
Details
Keywords
Nursyamsi Nursyamsi, Johannes Tarigan, Muhammad Aswin, Badorul Hisham Abu Bakar and Harianto Hardjasaputra
Damage to reinforced concrete (RC) structural elements is inevitable. Such damage can be the result of several factors, including aggressive environmental conditions, overloading…
Abstract
Purpose
Damage to reinforced concrete (RC) structural elements is inevitable. Such damage can be the result of several factors, including aggressive environmental conditions, overloading, inadequate design, poor work execution, fire, storm, earthquakes etc. Therefore, repairing and strengthening is one way to improve damaged structures, so that they can be reutilized. In this research, the use of an ultra high-performance fibre-reinforced concrete (UHPFRC) layer is proposed as a strengthening material to rehabilitate damaged-RC beams. Different strengthening schemes pertaining to the structural performance of the retrofitted RC beams due to the flexural load were investigated.
Design/methodology/approach
A total of 13 normal RC beams were prepared. All the beams were subjected to a four-point flexural test. One beam was selected as the control beam and tested to failure, whereas the remaining beams were tested under a load of up to 50% of the ultimate load capacity of the control beam. The damaged beams were then strengthened using a UHPFRC layer with two different schemes; strip-shape and U-shape schemes, before all the beams were tested to failure.
Findings
Based on the test results, the control beam and all strengthened beams failed in the flexural mode. Compared to the control beam, the damaged-RC beams strengthened using the strip-shape scheme provided an increase in the ultimate load capacity ranging from 14.50% to 43.48% (or an increase of 1.1450 to 1.4348 times), whereas for the U-shape scheme beams ranged from 48.70% to 149.37% (or an increase of 1.4870–2.4937 times). The U-shape scheme was more effective in rehabilitating the damaged-RC beams. The UHPFRC mixtures are workable, as well easy to place and cast into the formworks. Furthermore, the damaged-RC beams strengthened using strip-shape scheme and U-shape scheme generated ductility factors of greater than 4 and 3, respectively. According to Eurocode8, these values are suitable for seismically active regions. Therefore, the strengthened damaged-RC beams under this study can quite feasibly be used in such regions.
Research limitations/implications
Observations of crack patterns were not accompanied by measurements of crack widths due to the unavailability of a microcrack meter in the laboratory. The cost of the strengthening system application were not evaluated in this study, so the users should consider wisely related to the application of this method on the constructions.
Practical implications
Rehabilitation of the damaged-RC beams exhibited an adequate structural performance, where all strengthened RC beams fail in the flexural mode, as well as having increment in the failure load capacity and ductility. So, the used strengthening system in this study can be applied for the building construction in the seismic regions.
Social implications
Aside from equipment, application of this strengthening system need also the labours.
Originality/value
The use of sand blasting on the surfaces of the damaged-RC beams, as well as the application of UHPFRC layers of different thicknesses and shapes to strengthen the damaged-RC beams, provides a novel innovation in the strengthening of damaged-RC beams, which can be applicable to either bridge or building constructions.
Details
Keywords
Chun-Jian Su, Yong Li, De-Xing Yang, Zhen-Hua Bai, Rui Wang, Yu-Ting Lv and Jian-Gao Duan
The purpose of this study is to solve the key problem of the residual stress of strip in buckling and deviation during the continuous annealing process (CAP).
Abstract
Purpose
The purpose of this study is to solve the key problem of the residual stress of strip in buckling and deviation during the continuous annealing process (CAP).
Design/methodology/approach
Considering the one-to-one correspondence between deformation and residual stress, the strip was divided into multiple elements. To obtain the total deformation of each element, the influence model of some factors on the deformation of steel strip element was established. Then, according to the constitutive equation of residual stress and deformation, and the deformation coordination relation between strip elements, a set of calculation model, which is suitable for residual stress of strip during CAP was established, the model precision was verified by finite element method simulation, and the influences on residual stress of strip were also analyzed.
Findings
The weighted calculation of comparison between analytical results and simulation shows that the accuracy of the analytical method is within 10 per cent, which fully meets the requirements.
Originality/value
The different residual stress of steel strip can be displayed quickly and intuitively in the synchronous process segment according to this model, which is of great importance to the prevention of strip buckling and deviation.
Details
Keywords
Ke Zhong, Haizhong Wang and Caiyun Zhang
The purpose of this paper is to test the brand elongation effect which is defined as the impacts of the aspect ratio of logo on consumers’ temporal property assessment and brand…
Abstract
Purpose
The purpose of this paper is to test the brand elongation effect which is defined as the impacts of the aspect ratio of logo on consumers’ temporal property assessment and brand evaluation.
Design/methodology/approach
This paper provides a theory with experiments.
Findings
The brand elongation effect that strip-shaped logos can make consumers perceive temporal property longer than square-shaped logos has been testified with three pairs fictional logos and one pair real-life one. The valence of temporal property moderates the effect on evaluation of temporal property. The perceived temporal length mediated the shape effect on brand evaluation only when the temporal property is important (vs unimportant) for the product.
Research limitations/implications
This study only deals with the elongation effect of logos’ aspect ratio, without discussing the impact of color, angle/roundness or other graphic properties of logos on consumer attitudes.
Practical implications
This study not only provides empirical supports to update brand logos but also further illustrates that some subtle properties of logos can result in influences that are both significant and substantial.
Originality/value
This research enriches the literature of branding and metaphorical cognition. The findings of this study provide direct implications for brand managers to design logos and manage multi-shape brand logos.
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Dong Liu, Minghao Wang, Naiyu Fang, Ming Cong and Yu Du
Varied shapes and sizes of different products with irregular rough surface and fragile properties give a challenge to traditional contact gripping. Single Bernoulli grippers are…
Abstract
Purpose
Varied shapes and sizes of different products with irregular rough surface and fragile properties give a challenge to traditional contact gripping. Single Bernoulli grippers are not suited to handle fragile objects as the impact of center negative pressure force could result in large deformation and stress which damage the materials, and they are also have some limitations for gripping objects with different large and small shapes. Thus, this paper aims to design a non-contact gripper for soft, rough-surfaced and fragile objects gripping with multi Bernoulli heads, which have optimal structures and parameters.
Design/methodology/approach
The compressed air is ejected into four Bernoulli heads through radial and long flow channels, then passes through four strip-shaped narrow gaps after fully developing in the annular cavity to provide negative pressure. Based on the mathematic model and the computational model, the key structural parameters affecting the gripping performance are selected, and parameters optimization of the gripper is performed by computational fluid dynamics simulation analysis and performance evaluation. The orthogonal method is used and L16 orthogonal array is selected for experimental design and optimization. The characteristics of the designed gripper are tested from the aspects of pressure distribution and lifting force.
Findings
From the applications in gripping different objects, the designed non-contact gripper can grip varied shapes and sizes of soft, rough-surfaced, fragile and sliced objects with little effect of torque.
Originality/value
In this paper, a non-contact gripper is designed for handling soft, rough-surfaced and fragile objects based on the Bernoulli principle. A systematic approach, which consists of modeling, simulation, optimization and measurement is provided for the non-contact gripper design and tests.
Details
Keywords
Abstract
Details
Keywords
Fengwei Jing, Mengyang Zhang, Jie Li, Guozheng Xu and Jing Wang
Coil shape quality is the external representation of strip product quality, and it is also a direct reflection of strip production process level. This paper aims to predict the…
Abstract
Purpose
Coil shape quality is the external representation of strip product quality, and it is also a direct reflection of strip production process level. This paper aims to predict the coil shape results in advance based on the real-time data through the designed algorithm.
Design/methodology/approach
Aiming at the strip production scale and coil shape application requirements, this paper proposes a strip coil shape defects prediction algorithm based on Siamese semi-supervised denoising auto-encoder (DAE)-convolutional neural networks. The prediction algorithm first reconstructs the information eigenvectors using DAE, then combines the convolutional neural networks and skip connection to further process the eigenvectors and finally compares the eigenvectors with the full connect neural network and predicts the strip coil shape condition.
Findings
The performance of the model is further verified by using the coil shape data of a steel mill, and the results show that the overall prediction accuracy, recall rate and F-measure of the model are significantly better than other commonly used classification models, with each index exceeding 88%. In addition, the prediction results of the model for different steel grades strip coil shape are also very stable, and the model has strong generalization ability.
Originality/value
This research provides technical support for the adjustment and optimization of strip coil shape process based on the data-driven level, which helps to improve the production quality and intelligence level of hot strip continuous rolling.
Details
Keywords
Bibo Yao, Zhenhua Li, Baoren Teng and Jing Liu
Laser powder bed fusion (LPBF) can be used to fabricate complex extrusion die without the limitation of structures. Layer-by-layer processing leads to differences in…
Abstract
Purpose
Laser powder bed fusion (LPBF) can be used to fabricate complex extrusion die without the limitation of structures. Layer-by-layer processing leads to differences in microstructures and wear properties. This study aims to investigate the microstructure evolution and effects of tungsten carbide (WC) on the wear properties of LPBF-printed 18Ni300.
Design/methodology/approach
Economical spherical granulation-sintering-deoxygenation (GSD) WC-reinforced 18Ni300 steel matrix composites were produced by LPBF from powder mixtures of WC and 18Ni300. The effects of WC contents on anisotropic microstructures and wear properties of the composites were investigated.
Findings
The relative density is more than 99% for all the composites except 25% WC/18Ni300 composite. The grain sizes distributed on the top cross-section are smaller than those on the side cross-section. After adding WC particles, more high-angle grain boundaries and larger Schmid factor generate, and deformed grains decrease. With increasing WC contents, the hardness first decreases and then increases but the wear volume loss decreases. The side cross-section of the composite has higher hardness and better wear resistance. The 18Ni300 exhibits adhesive wear accompanying with abrasive wear, while plowing and fatigue wear are the predominant wear mechanisms of the composites.
Originality/value
Economical spherical GSD WC particles can be used to improve the wear resistance. The novel WC/18Ni300 composites are suitable for the application under the abrasive wear condition with low stress.
Details
Keywords
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder…
Abstract
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.
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The finite strip method has been shown to apply to many problems in continuum mechanics. Within the constraints of the method, it has been shown to be superior to the finite…
Abstract
The finite strip method has been shown to apply to many problems in continuum mechanics. Within the constraints of the method, it has been shown to be superior to the finite element method in terms of data preparation, program complexity and execution time. The finite strip method has been recently extended to groundwater flow problems. The orthogonality of appropriately selected shape functions gives the finite strip method its computational efficiency. The uncoupling achieved from this orthogonality also produces a numerical method which is intrinsically parallel. Consequently, additional efficiencies can be obtained in a parallel environment. Numerical studies of the finite strip method to model a two‐dimensional groundwater flow problem demonstrate the accuracy of the solution and the superior performance of the numerical procedure in a parallel environment.