Manufacturing Technology Today

T. Tamizharasan ¹, N. Senthil Kumar ²

Affiliations
1 T. R. P Engineering College, Tiruchirappalli, IN
2 Anna University of Technology, Tiruchirappalli, IN

Abstract

Modern manufacturing industries are concerned about producing quality components, with reduced production cost. To achieve this, the machining parameters and tools selected for machining a particular material should yield better results. During machining, flank wear occurring at the cutting insert is the predominant factor that causes poor surface finish, is responsible for the dimensional inaccuracy of the machined surface. In this work an attempt has been made to minimize flank wear of an uncoated carbide insert while machining AISI 1045 steel by finite element analysis. Three levels of machining and geometrical parameters, varied through 3 levels are chosen. An L₁₈ orthogonal array is selected based on Taguchi's design of experiment. Finite element analysis is carried out using DEFORM-2D, a simulation and analysis software and the output quality characteristics are analyzed using signal-to-noise ratio and analysis of variance (ANOVA). A validation simulation analysis is performed based on the optimum condition obtained.

Keywords

Machining Parameter, Tool Geometry, Flank Wear, FE Analysis, DEFORM-2D.

Full Text

     

A. Noorul Haq ¹, T. Tamizharasan ¹

Affiliations
1 Department of Production Engg., National Institute of Technology, Thiruchirappalli-620015, Tamil Nadu, IN

Abstract

In this investigation, the effect of workpiece hardness on flank wear of cutting tool, electrical energy consumption and roughness of machined surface in dry turning operation at two different cutting speeds are experimentally investigated. The dry turning experiments are conducted with coated carbide inserts. The workpieces are selected with ten different hardness values ranging from 10 to 55HRC. The two levels of cutting speed selected are 100m/min. and 50m/min. and the other parameters such as feed rate and depth of cut are maintained constant at 0.3mm/rev. and 0.5mm respectively. Each experiment is conducted for an experimentally determined duration of 31 minutes and at the end of each experiment, the flank wear, electrical energy consumption and arithmetic average surface roughness of machined surface are measured and recorded. The flank wear is significantly affected by the hardness of workpiece and cutting speed. This analysis provides guidelines on tool and workpiece material selection in finish dry turning operations for minimizing tool wear and energy consumption by maintaining the surface roughness value at the desired level.

Full Text

     

T. Tamizharasan ¹, J. Kingston Barnabas ²

Affiliations
1 Dept. of Mech. Engg., Periyar Maniammai University, Thanjavur, IN
2 Dept. of Mech. Engg., Anjalai Ammal Mahalingam Engg. College, Kovilvenni, Tiruvarur, IN

Abstract

This analysis focuses on the online monitoring of flank wear in turning from the experimentally observed Acoustic Ernission signal. It is used as one of the indirect methods of monitoring flank wear in turning. As per the technique, Taguchi’s “Design of Experiments”, the minimum number of experiments to be conducted in this analysis is calculated, and the turning operations are performed as per the machining conditions shown in the orthogonal array. Since the direct measurement of flank wear at regular intervals of time during machining consumes more man and machine hours, the Acoustic Emission signal developed in the machining area is continuously recorded during machining as an alternative to the flank wear. The corresponding flank wear in all the test conditions with respect to time of 300 seconds are observed and recorded. When the value of Acoustic Emission signal tends to reach the unsafe limit corresponding to the flank wear of above 0.2mm, the operator is alerted to stop the process so as to replace the tool. This technique minimizes the tool cost without sacrificing the quality of the product. In this study, the empirical modeling technique using “Regression analysis” is also incorporated to develop the linear and non linear models for all test conditions. The experimental, optimized and predicted values of flank wear are compared and correlated with the experimental Acoustic Emission signal.

Full Text

     

D. Prakash ¹, T. Tamizharasan ²

Affiliations
1 Dept. of Mechanical Engineering, Anjalai Ammal Mahalingam Engg. College, Kovilvenni - 614 403, Tamil Nadu, IN
2 Dept. of Production Engineering, National Institute of Technology, Trichy-620 015, Tamil Nadu, IN

Abstract

In this paper, weld quality is improved in the gas welding of mild steel plates by using Taguchi’s Design of Experiment (DOE) technique. The strength of the welded joint is strongly governed by the involving process parameters and filler rod selection. Though many factors affect the weld strength, present paper focuses only on the weld speed, oxygen-acetylene gas pressure, torch angle, gap between weld plate and torch tip and gap between weld plates. These parameters are varied to three levels of values and hence L,g orthogonal array is employed. The sixteen different combinations of experiment are conducted in a special type of pneumatic system designed along with a torch holder to control the process parameters accurately. The weld specimens are tested in the Vickers hardness tester and Universal-testing machine. The best value of the weld process parameters is identified from the S/N curves. A validation experiment is also conducted and it is predicted that, the strength of the welded joint is improved by about 2%. ANOVA calculations are performed to identify the individual effect of process parameters on the weld quality. Finally, empirical models are developed to predict the weld strength on the basis of tensile strength and hardness value. The developed empirical models are having good agreement with the experimental results.

Full Text

     

A. Noorul Haq ¹, T. Tamizharasan ¹

Affiliations
1 Department of Production Engineering, National Institute of Technology, Tiruchirappalli-620015, IN

Abstract

The cutting tool life has significant importance in metal turning operation. So the cutting tool life for the maximum permissible value o f flank wear (0.2 mm) is analyzed in this study, in this paper, the Taguchi methodology of optimization is applied to optimize the cutting parameters in turning when machining engine crank pin material with CBN cutting tool inserts. The turning parameters evaluated are, cutting speed, feed rate and depth of cut. The objectives of this study are maximization o f tool life and minimization of specific energy. An orthogonal array, signal-to-noise (S/N) ratio and the S/N charts are employed in order to analyze the individual and interactive effects of the selected turning parameters on the objectives. This result o f the analysis shows the optimal combination of parameters for higher tool life, lower specific energy and good surface finish. By using Taguchi's Design of Experiments (DOE), the other significant effects such as the interaction among the various turning parameters are also analyzed. The Taguchi method is more suitable to optimize the turning parameters as compared with a full factorial design.

Full Text

     

A. Noorul Haq ¹, T. Tamizharasan ¹

Affiliations
1 Department of Production Engineering, National Institute of Technology, Tiruchirappalli-620015, Tamilnadu, IN

Abstract

The life of cutting tool in metal cutting plays an important role in the quality and cost of product. In this present study, an empirical model for the prediction of cutting tool life in turning operation is developed. The performance of the metal turning has been studied under varying operating conditions such as speed of cutting, feed rate and depth of cut. This study describes the operation of the experimental system and presents the measured data. The required turning operation is performed on a lathe machine with hardened material used as engine crank pin for work piece and Polycrystalline Cubic Boron Nitride (PCBN) for cutting tool. For developing the required empirical model. Linear Regression, Linear Cross Product Regression, Log Transformed Linear Regression and Log Transformed Cross Product Regression are employed. The values predicted from various empirical models are compared with the experimental values and concluded that which model is best fit for the objective. In general, the metal turning experiments and statistical tests demonstrate that "the empirical models developed in this work are best fit with acceptable range of deviations".

Full Text