A Conceptual Model of Integrated Management System on the Organizational Excellence of Pubic Organization

Purpose: Integrated management system (IMS) assumes a crucial part in the administration of hierarchical issues and issues that connect with work whether formal or casual.   Theoretical Framework: The way that the IMS consolidates different administration frameworks that all alone guarantee positive result creates it a brilliant framework that can ensure authoritative greatness. Despite the fact that that is the situation, the contention has been how much might IMS at any point add to the accomplishment of hierarchical greatness? In that capacity, this calculated structure looks for feature the effect of IMS execution in associations.   Design/ Methodology/ Approach: IMS impact on hierarchical greatness was resolved in view of client center, development practices and association responsibility. Concerning IMS impact on association advancement, the perspectives that were given a lot of thought included process development, item development, innovation development and showcasing development.   Finding: Conversation on IMS was generally founded on how it connects with association development and greatness and its impact on authoritative culture and the most effective way of carrying out the IMS in an association. Speculation in light of finding out the degree of IMS effect on association development and greatness and how they interrelate.   Implications: The results of this study approves the calculated model that encourages mindfulness and execution of IMS in associations. Also, the result of this examination gives observational proof that associations who are zeroing in on greatness through IMS might make progress in the work.   Originality: This exploration applied review reports and calculated development model to quantify the degree of carrying out IMS, which incorporates the monetary, ecological, and security factors (for example ISO 9001 for quality administration frameworks (QMS), ISO 14001 for ecological administration frameworks (EMS) and ISO 45001 for Occupational Health and Safety the executives into a solitary measure to characterize the effect of feasible execution of IMS on hierarchical greatness enough.

Mathematical Modeling of Surface Roughness in Surface Grinding Operation

A mathematical model of the surface roughness has been developed by using response surface methodology (RSM) in grinding of AISI D2 cold work tool steels. Analysis of variance (ANOVA) was used to check the validity of the model. Low and high value for work speed and feed rate are decided from design of experiment. The influences of all machining parameters on surface roughness have been analyzed based on the developed mathematical model. The developed prediction equation shows that both the feed rate and work speed are the most important factor that influences the surface roughness. The surface roughness was found to be the lowers with the used of low feed rate and low work speed. Accuracy of the best model was proved with the testing data

Internal flow behaviour and microstructural evolution of the bobbin-FSW welds: thermomechanical comparison between 1xxx and 3xxx aluminium grades

The influences of processing parameters and tool feature on the microstructure of AA1100 and AA3003 aluminium alloys were investigated using bobbin friction stir welding (BFSW). The research includes flow visualization and microstructural evolution of the weld texture using the metallographic measurement method. Results indicated that the operational parameters of the welding (e.g. feed rate, rotating speed) and the geometry of the tool can directly affect the flow patterns of the weld structure. The microscopic details revealed by the optical and electron microscope imply the dynamic recrystallization including grain refinement and precipitation mechanisms within the stirring zone of the weld region. The microscopic observations for the weld samples show a better performance of the fully-featured tool (tri-flat threaded pin and scrolled shoulders) compared to the simple tool without inscribed surface features. The fully-featured tool resulted in a more uniform thermomechanical plastic deformation within the weld structure along with the precipitation hardening and the homogeneity of the microstructure

Fixed bobbin friction stir welding of marine grade aluminium.

PROBLEM - The bobbin friction stir welding (BFSW) process has potential benefits for welding thin sheet aluminium alloy. The main benefits of friction stir welding over conventional thermal welding processes are minimisation of energy usage, no need for consumables, potential for good weld quality without porosity, no fumes, minimal adverse environmental effects (green), minimal waste (lean), and reduced threats to personal health and safety. The BFSW process has further advantages over conventional friction stir welding (CFSW) in the reduction of welding forces, faster welding, and less fixturing. It is especially attractive to industries that join thin sheet material, e.g. boat-building. The industrial need for this project arose from the desire to apply the technology at a ship manufacturing company, INCAT located in Hobart, Tasmania, Australia. However there are peculiar difficulties with the specific grade of material used in this industry, namely thin sheet aluminium Al6082-T6. Early efforts with a portable friction stir welding machine identified the process to have low repeatability and reproducibility, i.e. process-instability. There are a large number of process variables and situational factors that affect weld quality, and many of these are covert. This is also the reason for divergent recommendations in the literature for process settings. PURPOSE - The main purpose of this research was to identify covert variables and better understand their potentially adverse effects on weld quality. Therefore, this thesis investigated the hidden variables and their interactions. Developing this knowledge is a necessity for making reliable and repeatable welds for industrial application. APPROACH - An explorative approach that focused on the functional perspective was taken. An extensive empirical testing programme was undertaken to identify the variables and their effects. In the process a force platform and BFSW tools were designed and built. A variety of machine platforms were used, namely portable friction stir welding, manual milling machine and computer numerical control (CNC) milling machine. The trials were grouped into 14 test plans. These are tool shoulder gap, spindle and travel speed, tool features, machines, tool fixation, machinery, welding direction, plate size (width and dimension), support insulation, tool materials, substrate properties and fixation. For the welded plates besides visual inspection of the weld, current, force, and temperature were measured. The Fourier transform was used to analyse the frequency response of machines. Also the welded samples were tested to the maritime standards of Det Norske Veritas (DNV). A number of relationships of causality were identified whereby certain variables affected weld quality. A model was developed to represent the proposed causality using the IDEF0 systems engineering method. FINDINGS - From these trials six main variables have been identified. These are tool features, spindle speed, travel speed, shoulder gap compression, machine variability, tool and substrate fixation. A rigid system is required for a consistent weld results. Under this condition, full pin features (threads and flats) need to be used to balance the adverse effects of individual features. It has been shown that fabricated bobbin tools with sharp edges can cause cuts and digging thus this feature should be avoided. Additionally, the substrate should have continuous interaction with the tool so the shoulder interference needs to be fixed and well-controlled. It is found that the compression generated by the shoulder towards the substrate helps material grabbing for better tool-substrate interaction. It is also shown that tool entry causes ejection of material and hence an enduring mass deficit, which manifests as a characteristic tunnel defect. The new explanation of the formation, origin and location of this defect has been explained. Material transportation mechanisms within the weld have been elucidated. It is also found that the role of the travel speed is not only to control heat generation but also for replacing the deficit material. Additionally, heat supplied to the weld depends not only on thickness, but also the width of the plate. Different types of machine cause an interaction in the material flow through their controller strategies. Jerking motion can occur at a slow travel speed, which also alters the way material is being transported. The Fourier transform (FFT) has been used to identify the characteristics of good and bad BFSW welds. This has the potential to be expanded for real-time process control. IMPLICATIONS - Tool deflection and positioning, material flow and availability are identified as affecting weld quality through stated mechanisms. The impact is even more severe when involving thin-plate aluminium. For the industry to successfully adopt this technology the process typically needs tight control of shoulder gap, tool strength and stiffness, feature fabrication, substrate and tool fixation. Additionally spindle and travel speed need to be adjusted not only based on the type of materials and thickness, but also the width, type of machine and method of tool entry. ORIGINALITY - New data are presented, which lead to new insights into the welding mechanics, production settings, material transportation and weld defects for BFSW on thin sheet material. The conventional idea that the welding tool has a semi-steady interaction with the substrate is not supported. Instead the interaction is highly dynamic, and this materially affects the weld-quality, especially in the difficult-to-weld material under examination. Factors such as shoulder gap, tool and substrate fixation compliance and machine types emerge as variables that need to be given attention in the selection of process parameters. The causal relationships have been represented in a conceptual model using an IDEF0 system approach. This study has made several original contributions to the body of knowledge. First is the identification of previously hidden variables that effect weld formation for the fixed gap BFSW process. The second contribution is a new way of understanding the material transportation mechanics within the weld. This includes the flow around the pin in the plane of the weld, the vertical transportation of material up the pin, the formation of turbulent-like knit lines at the advancing side, and the formation of tunnel defects. Also included here is a new understanding of how material deficit arises at tool entry and exit, and from flash/chips, and how this contributes to the tunnel weld defect. In addition, new understandings of the role of feed rate have been identified. Related to the material transportation, the work has also identified the importance of an interference fit between the substrate and tool. A third contribution is the identification of the dynamic interaction between tool and substrate. This identifies the important role rigidity plays. Associated with this is the identification of frequency characteristics of the motors under load. The fourth contribution is identification of the specific process settings for the difficult-to-weld material of AL6082-T6. The fifth contribution is the development of a novel method of fabricating bobbin friction stir welding tools as embodied in a patent application

Mathematical Modeling of Surface Roughness in Surface Grinding Operation

A mathematical model of the surface roughness has been developed by using response surface methodology (RSM) in grinding of AISI D2 cold work tool steels. Analysis of variance (ANOVA) was used to check the validity of the model. Low and high value for work speed and feed rate are decided from design of experiment. The influences of all machining parameters on surface roughness have been analyzed based on the developed mathematical model. The developed prediction equation shows that both the feed rate and work speed are the most important factor that influences the surface roughness. The surface roughness was found to be the lowers with the used of low feed rate and low work speed. Accuracy of the best model was proved with the testing data

Evaluation of current, force and temperature signals on welding formation of bobbin friction stir welded AA1100

Understanding process response through measuring process signal provides onsite information in the area of process monitoring, which saves time and costs. The type of signals depends upon the type of process, equipment and machines used through sensors attached on the equipment used in the process. This is an important method for detecting changes in the process that reflect the condition or quality of the weld. The benefits of this method, however, has not been well performed for Bobbin friction welding. This process is different from conventional friction welding due to the different process set-up in term of tooling and parameters, hence the need to evaluate the signal response. Consequently, signal measuring for welding plate AA1100 was carried out. Tool rotation ranged from 750 rpm to 950 rpm with a fixed travel rate of 130 mm/min on a CNC milling machine and a fixed spacing tool. During the joining process, welding temperature, current consumption and welding force were measured. The resulting data were then plotted on the X-Y axis chart and mapped using the welded plate identifying the welding phase. From the welding force and current measurement, it is found that high force and current is detected at the tool entry phase and exit. As the tool moves towards the end of the plate, the temperature increased. The highest current and strength are measured when the spindle speed is at the lowest, while the highest temperature is at the fastest spindle speed In weld phase a current of © The Authors 2021

Effects of ColdArc welding parameters on the tensile strengths of high strength steel plate investigated using the Taguchi approach

The objective of this study is to investigate the effect of process parameters on ColdArc welding of high strength steel plate using 1.2 mm diameter mild steel welding wire. A Taguchi Design of Experiments (DOE) method with grey relational analysis approach was selected for data collection and optimization. 9 experiments were conducted following the L9 (33) Taguchi Orthogonal Array Design. The best result from the experiments for tensile strength was obtained for welding parameters of 70 A (current), 17.6 V (voltage) and 800 mm/min welding speed. Based on the results, the Taguchi analysis predicted the optimised tensile strength would be obtained when the welding current, welding voltage and speed are at 70V, 17.6A and 600 mm/min, respectively. Thus, most significant parameters for tensile properties of cold rolled steel is welding speed (37%), voltage (34 %) and current (28%). These factors are critical in determining the tensile strength, where increasing the welding speed reduces the heat input. However, decreasing the heat input by lowering the welding voltage resulted in bad weld bead formation. © Universiti Malaysia Pahang, Malaysi