Process Information Model for Sheet Metal Operations

International audienceThe paper extracts the process parameters from a sheet metal part model (B-Rep). These process parameters can be used in sheet metal manufacturing to control the manufacturing operations. By extracting these process parameters required for manufacturing, CAM program can be generated automatically using the part model and resource information. A Product model is generated in modeling software and converted into STEP file which is used for extracting B-Rep which interned is used to classify and extract feature by using sheet metal feature recognition module. The feature edges are classified as CEEs, IEEs, CIEs and IIEs based on topological properties. Database is created for material properties of the sheet metal and machine tools required to manufacture features in a part model. The extracted feature, feature's edge information and resource information are then used to compute process parameters and values required to control manufacturing operations. The extracted feature, feature's edge information, resource information and process parameters are the integral components of the proposed process information model for sheet metal operations

Numerical modelling and simulation in sheet metal forming

The application of numerical modelling and simulation in manufacturing technologies is looking back over about a 20–30 years history. In recent years, the role of modelling and simulation in engineering and in manufacturing industry has been continuously increasing. It is well known that during manufacturing processes simultaneous the effect of many different parameters can be observed. This is the reason why in former years, detailed analysis of manufacturing processes could have been done only by time-consuming and expensive trial-and-error methods. Due to the recent developments in the methods of modelling and simulation, as well as in computational facilities, modelling and simulation has become an everyday tool in engineering practice. Besides the aforementioned facts, the emerging role of modelling and simulation can also be explained by the growing globalisation and competition of the world market requiring shorter lead times and more cost effective solutions. In spite the enormous development of hardware and software facilities, the exclusive use of numerical modelling still seems to be very time- and cost consuming, and there is still often a high scepticism about the results among industrialists. Therefore, the purpose of this paper is to overview the present situation of numerical modelling and simulation in sheet metal forming, mainly from the viewpoint of scientific research and industrial applications

Recent Achievements in Numerical Simulation in Sheet Metal Forming Processes

Purpose of this paper: During the recent 10-15 years, Computer Aided Process Planning and Die Design evolved as one of the most important engineering tools in sheet metal forming, particularly in the automotive industry. This emerging role is strongly emphasized by the rapid development of Finite Element Modelling, as well. The purpose of this paper is to give a general overview about the recent achievements in this very important field of sheet metal forming and to introduce some special results in this development activity. Design/methodology/approach: Concerning the CAE activities in sheet metal forming, there are two main approaches: one of them may be regarded as knowledge based process planning, whilst the other as simulation based process planning. The author attempts to integrate these two separate developments in knowledge and simulation based approach by linking commercial CAD and FEM systems. Findings: Applying the above approach a more powerful and efficient process planning and die design solution can be achieved radically reducing the time and cost of product development cycle and improving product quality. Research limitations: Due to the different modelling approaches in CAD and FEM systems, the biggest challenge is to enhance the robustness of data exchange capabilities between various systems to provide an even more streamlined information flow. Practical implications: The proposed integrated solutions have great practical importance to improve the global competitiveness of sheet metal forming in the very important segment of industry. Originality/value: The concept described in this paper may have specific value both for process planning and die design engineers

Numerical explicit analysis of hole flanging by single-stage incremental forming

The use of Single-Point Incremental Forming (SPIF) technology in hole flanging operations using multi-stages strategies have been widely studied in the last few years. However, these strategies are very time-consuming, limiting its industrial application.In a very recent work of the authors, the capability of SPIF process to successfully perform hole-flanges using a single-stage strategy has been experimentally investigated. The aim of the present work is to develop a numerical model of this process to beable to predict the sheet failure as a function of the size of the pre-cut hole. The numerical results are compared and discussed in the light of experimental tests over AA7075-O metal sheets with 1.6mm thickness.Ministerio de Economía y Competitividad DPI2015-64047-

Tolerancing and Sheet Bending in Small Batch Part Manufacturing

Tolerances indicate geometrical limits between which a component is expected to perform its function adequately. They are used for instance for set-up selection in process planning and for inspection. Tolerances must be accounted for in sequencing and positioning procedures for bending of sheet metal parts. In bending, the shape of a part changes not only locally, but globally as well. Therefore, sheet metal part manufacturing presents some specific problems as regards reasoning about tolerances. The paper focuses on the interpretation and conversion of tolerances as part of a sequencing procedure for bending to be used in an integrated CAPP system

Integrated Process Simulation and Die Design in Sheet Metal Forming

During the recent 10-15 years, Computer Aided Process Planning and Die Design evolved as one of the most important engineering tools in sheet metal forming, particularly in the automotive industry. This emerging role is strongly emphasized by the rapid development of Finite Element Modelling, as well. The purpose of this paper is to give a general overview about the recent achievements in this very important field of sheet metal forming and to introduce some special results in this development activity. Therefore, in this paper, an integrated process simulation and die design system developed at the University of Miskolc, Department of Mechanical Engineering will be analysed. The proposed integrated solutions have great practical importance to improve the global competitiveness of sheet metal forming in the very important segment of industry. The concept described in this paper may have specific value both for process planning and die design engineers

Epidemiological and awareness study of tuberculosis in Batu Pahat, Johor, Malaysia

Tuberculosis (TB) remains one of the serious infectious diseases and has been characterized worldwide as an epidemic by World Health Organization (WHO). TB is still a public health problem in Malaysia. Baseline information on the disease situation is one of the prerequisites for the development of appropriate control measures. The cornerstone in proper management of TB patients is ensuring high awareness in communities about TB. Thus the current research is directed to investigate the epidemiology of TB, determined the level of public awareness of TB and some factors that are responsible for the emergence of TB. Retrospective method was used for collecting epidemiological data from the Batu Pahat chest clinic. All registered TB patients (total of 1213 patients) from 2008 to 2013 in Batu Pahat Chest Clinic were included in the study. On the other hand, the awareness study was carried out by the use of questionnaires. A two-stage cluster sampling method was used. 600 respondents were targeted which form the study sample. However, 498 questionnaires were returned. Descriptive data analysis was employed to describe the results in frequency and percentage distribution. It was discovered that there was an annually increase in TB incidence with pulmonary TB the most common infection in Batu Pahat. Almost all (92.7%) the TB cases were new. On the other hand, majority (87.0%) of respondents have heard about TB. Common symptoms identified by respondents were coughing for over 2 weeks (51.8%), hemoptysis (49.2%) and difficulty in breathing (50.2%). Smoking cigarette (74.3%), living with individual having chronic cough (71.5%) and HIV/AIDS (65.7%) were the common risk factors of TB identified by respondents. Most of the respondents (83.5%) were aware of the existence of TB drugs. However, the standard DOTs treatment duration of 6-9 months was identified by few (12.4%) respondents. This research provided information regarding TB status in Batu Pahat. The level of awareness among Batu Pahat general public about TB is fairly good. Meanwhile, more need to be done especially on diabetes as the risk factors of TB and treatment duration

To develop a new mineral carbonation process that have a high efficiency in CO2 absorption into industry slag using low energy mechanical milling

Increase in the CO2 emission in atmosphere due to the combustion of fossil fuels has caused serious global warming. Electricity generation, tranportation, and industrial waste are the main sectors indentified to contribute to the emission of CO2 in Malaysia. In dealing with this issue, the absorption of CO2 into industrial waste was experimentally studied by the utilization of mechanical grinding method. This research is to aim a development of new mineral carbonation process that has a high efficiency in the capture and storage of CO2 with low energy consumption. In the first stage of this study, the behavior of CO2 absorption on electric arc furnace and ladle furnace slag was studied by low energy mechanical milling It was found that the absorption is occured during milling. CO2 was stored into the slag mainly as CaCO3. Thus this indicates that the CO2 can be stored permanently inside the slag with this method. In the next stage, the effect of dissolution of metal element into water on the behavior of CO2 absorption was investigated by leaching test experiment. It was found that , concentration value of Fe in pure water is higher but in river water the concentration is lower, the dissolve concentration decreased with the increased in the number of the leaching time. Concentration will be increased at the earlier stage before it decreased at final of concentration. This case because the liquid became saturated and cannot be to dissolved. After the pH steeply increased gradually at an early stage of the elution of slag, it slightly decreased. The pH decreased with the increased in the number of elution. The changes of pH in leaching test it seemed to depend on the content of CaO in the slag. For mechanism of CO2 absorption, morphological change of slag were study and the slag were characteried by using XRD, FE-SEM, and EDS