Optimisation of grinding parameters for wheel loading and dressing
Grinding is a finishing process often used to produce desired surface roughness with required precision and quality. The performance of grinding wheel significantly depends on the nature of the wheel, morphology of the abrasive grits and the grinding parameters namely speed, feed and depth of cut. As the wheel is performing its grinding operation, its cutting surface is being loaded with metal particles of the workpiece. This wheel loading also affects the surface finish of the workpiece. Hence monitoring the grinding wheel loading and dressing at proper time intervals becomes mandatory to get the desired surface finish. In the quest of developing a low cost monitoring system, it is good enough to analyse the wheel loading on widely used metal specimens such as mild steel, HCHCr steel and aluminium under optimised cutting conditions using the conventional silicon carbide and aluminium oxide wheels for better evaluation of the results. In this work the grinding parameters are optimised by using ANOVA technique. A full factorial experiment was carried out at 5% level of significance, i.e. at 95% confidence level.
Optimal Selection Of Machining Parameters In CNC Turning Process Of EN-31 Using Intelligent Hybrid Decision Making Tools
Abstract Nowadays numerical and Artificial Neural Networks (ANN) methods are widely used for both modeling and optimizing the performance of the manufacturing technologies. Optimum machining parameters are of great concern in manufacturing environments, where economy of machining operation plays a key role in competitiveness in the market. Therefore the present research is aimed at finding the optimal process parameters for turning process of EN-31. EN-31 is chosen as the work material because of its wide applicability as material for Ball and roller bearings, spinning tools, Beading rolls, Punches and dies and by its character it has very high resistance nature against wear and can be used for components subjected to severe abrasion, wear or high surface loading. Turning is used to produce rotational, typically axi-symmetric, parts that have many features, such as holes, grooves, threads, tapers, various diameter steps, and even contoured surfaces. Turning is also commonly used as a secondary process to add or refine features on parts that were manufactured using a different process. Due to the high tolerances and surface finishes that turning can offer, it is ideal for adding precision rotational features to a part whose basic shape has already been formed. Keeping in view of the importance of turning process, it is very important to automate the process. In order to automate the system or process it is essential to find the optimal process parameters. Hence intelligent hybrid decision making tools are applied to find the optimal process parameters. First the experiments were conducted as per the design of experiments, and then ANN is applied to predict the models for the chosen output responses. Later the models after testing for its adequacy using ANOVA Analysis, they may be chosen for subsequent optimization of the process parameters using Evolutionary techniques. The obtained optimal process parameters will be used to automate the process
Numerical Simulation of Induction Heating Process of Continuous Casting Slab
Compared with traditional blazing furnace, the Continuous Casting-Direct Rolling is an advanced manufacturing steel technology, which can reduce energy waste, decrease pollution and enhance efficiency. The characteristics of steels during induction heating are complex, the change of material properties with temperature makes exact analysis methods very difficult to implement. Therefore, a powerful computer aided numerical tool (i.e., finite difference analysis) is selected to numerically model the induction heating process in this paper. The mathematic model coupling with electromagnetic field and thermal field was established, and it was solved by finite difference method (FDM), thus the slab temperature distribution and its variation with time were obtained, and the characteristics in whole induction heating process were studied. To validate the program feasible, the results were evaluated and compared with experiment results, which showed that the simulation results are reliable and effective. The skin effect in heating process from the two results was studied and demonstrated, the temperature change caused by different parameters such as the induced power intensity and the corner radian were also presented, which indicate that the slab temperature can be heated uniformly through adjusting these parameters, thus the continuous casting slab can meet the rolling requirement.