Manufacturing Technology Today

A. S. Selvakumar ¹, K. Kalaichelvan ², S. Venkataswamy ³, S. Natarajan ⁴

Affiliations
1 Dept. of Mechanical Engg., B S Abdur Rahman University, Vandalur, Chennai, IN
2 Dept. of Prod. Engg., M. I. T, Anna University, Chennai, IN
3 B S Abdur Rahman University, Vandalur, Chennai, IN
4 Dept. of Mechanical Engg., Anna University, Chennai, IN

Abstract

Hydro forming is a method of deforming sheet metal and tubular materials with the help of pressurized fluid medium using closed dies. In tube hydro forming process an internal fluid medium (inside the tube) serves as the forming medium and the tube is bulged into the desired shape through simultaneous application of axial feed and internal pressure. This paper aims to study the formability characteristic for aluminum tubular materials (A9 6063) for expansion zone geometry by considering various parameters such as axial feed, fluid medium, and semi cone angle of 20°. The formability of tube material was evaluated by varying the process parameters. In the experimental work, the tubular specimen was placed between the two halves of a split die and filled with oil as the forming medium. This tooling was mounted on a hydraulic press. The punch was advanced into the tube to increase the fluid pressure and to provide axial feed of the tube. The optimal expansion zone geometry was identified by various experimental trials, to get flaw free component.

Keywords

Formability, Tube Hydro Forming, Expansion Zone, Pressurised Fluid Medium.

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C. Dhandapani ¹, R. Sivaramakrishnan ², K. Kalaichelvan ²

Affiliations
1 Dept. of Mechanical Engg., Rajagopal Polytechnic College, Gudiyattam-632602, Tamil Nadu, IN
2 Dept. of Production Technology, MIT Campus, Anna University, Chennai-600044, IN

Abstract

This article presents modelling, simulation, kinematic and workspace analysis of a triglide type of three degrees of freedom parallel manipulator actuated by screw pairs and spherical pairs. A fabricated model of the manipulator has been used for experimental analysis to find the angular tilt of moving platform. A computer program with suitable algorithms is developed to find the displacement of the nuts of the screw pairs and the kinematic analysis is performed. In order to further validate the model the software package ADAMS (Automatic Dynamic Analysis of Mechanical Systems) is used to simulate to verify the displacement and angular tilt of the moving platform. The results obtained from experimental, analytical and simulation methods are verified and found to be closer in all the three cases. This mechanism of parallel manipulator, no doubt shall find its way for performing applications like machining inclined holes, contour milling and angular machining with accuracy and precision.

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K. Kalaichelvan ¹, R. Sivaramakrishnan ¹, K. Murugaraj ¹, A. Joseph Stanley ¹

Affiliations
1 MIT Campus, Anna University, Chromepet, Chennai - 44, IN

Abstract

This paper focuses on formability value of aluminium alloy sheet in the stretch forming operation. The formability of materials can be varied with respect to different heat treatment processes. Aluminium alloy sheets were prepared for the required size under cold rolled, polymer quenched and annealed conditions. A hemispherical punch and ring die were designed and fabricated for performing the stretch forming operations. The surface of each aluminium alloy sheet was imprinted with circular grid pattern of diameter 5 mm and these sheets were stretch formed by using the punch and die. The change in grid pattern after deformation were measured and analysed for major and minor strain values. From these values a formability limit diagram was constructed for each heat treatment conditions. From the forming limit diagram it is found that the annealed and polymer quenched aluminium alloy sheets have good formability. For increasing the formability value of the Aluminium alloy sheets, the stretch forming of the annealed specimen was repeated by applying the proper lubricant (SAE 40) in between the work and punch surface. It is found 2% increase in major strain in lubricating condition. The tensile strength of the sheet metal is found in UTM with constant cross head speed. The tensile strength of polymer quenched aluminium alloy sheet is placed very close to the cold rolled one. Hence polymer quenched aluminium sheets are recommended for making automobile components.

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M. Vivek Dev ¹, R. Sivaramakrishnan ¹, K. Kalaichelvan ¹, R. Dhanraj ²

Affiliations
1 Dept, of Production Technology, M.l.T.Campus, Anna University, Chromepet, Chennai-6000 44, IN
2 Centre for Aerospace Engineering, M.l.T. Campus, Anna University, Chromepet, Chennai -6000 44, IN

Abstract

This paper focuses on the modeling, simulation, and analysis of kinematics & force of a three Degrees Of Freedom (DOF) parallel manipulator that can be used in the applications such as drilling inclined holes, contour milling and angular machining etc. The entire arrangement of three Degrees of freedom parallel manipulator is modeled using 'ADAMS' software package and simulation & analysis were carried out. The position kinematics of this mechanism have been carried out experimentally and the results are verified with the 'ADAMS' package results. An algorithm has been developed and a software program is written to find out the horizontal displacement of nut and the necessary cylinders to be actuated for the required angle of tilt of the platform. The torque and thrust force values during drilling were calculated and checked for withstanding in the moving platform.. From the ADAMS package, the forces acting in the links and joints can be found out graphically. From these force graphs, the stresses and strains acting in the three links before and after actuation are calculated and the results were analyzed.

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