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In a fastening system when there is a small misalignment of the holes, the holes are enlarged to align the axes and a next size fastener is used to fit the joint. But when the misalignment is large then the enlargement need to be proportionally large. In this case a bushing is press fit onto the hole to handle the fastening. If we press fit a bushing, it generates residual stresses in the panel. These residual stresses reduce the damage life of the components on which the bushings were press fit. In the aircraft engine nacelle components the damage life is very critical in various failure conditions such as fan blade out condition, wind milling and bird strike. It increases the flight time in these events. Here four different case studies were considered to study the damage life of the aircraft components made of Aluminum or composite material.

Forging is a metal forming process involving shaping of metal by the application of compressive forces using hammer or press. Forging load of equipment is an important function of forging process and the prediction of the same is essential for selection of appropriate equipment. In this study a hot forging material i.e. 42CrMo4 steel is selected which is used in automotive components like axle, crank shaft. Hot forging experiments at 750°C are carried out on cylindrical specimens of aspect ratio 0.75 and 1.5 with true height strain (ln (ho/hf)) of 0.6. Forging load for the experiments is calculated using slab and upper bound deformation models as well as Metal forming simulation using commercially available FEA software. The upper bound models with 30% deviation from the simulation results are found to be more accurate compared to the slab models.

The present work is concentrated to study the effect of varying inlet pressures on the dynamics of the suction valve obtained from a hermetic reciprocating compressor. The effect of valve functioning on the efficiency of a compressor is highly acceptable. Rather than the delivery valve, the suction valve has a significant impact on the compressor efficiency. The reed valve in a hermetic compressor is a cantilever type arrangement. The valve operates due to the pressure difference between the suction muffler and the cylinder. The numerical analysis which includes Fluid-structure interaction is used in the present study. The flow and structural domain employed in the present study are modelled with Solidworks 15.0. The fluid structure interaction analysis is a combination of ANSYS Fluent and ANSYS structural. These two are coupled with a system coupling in ANSYS Workbench 16.0. The numerical results obtained from the simulation are validated with the experimental data.

The increasing demand for light weighting products due to introduction of various standards and norms for controlling CO2 emissions and to meet the customer requirement of low cost with higher strength and rigidity of product in automotive industry, sheet metal manufacturing technique is adopted for automotive steering yoke for light commercial vehicle. Currently forged yokes are used for higher strength requirement, while sheet metal yokes are being used for small tonnage vehicle. The attempt has been made to improve overall strength and rigidity of the yoke produced by sheet metal operation using SAPH 440 steel with 6.5mm thickness for light commercial vehicle segments. The major challenge identified for this development was developing such a high strength and thickness material with consistency of dimension during forming process and meeting the torsional strength requirement of 500 Nm.

The use of thermoplastics in various fields like aerospace, automotive, medical and packaging industries is growing day by day, due to their light weight and compactness. In some instances, the plastic components are required to be welded. In this research study, process parameters used for the ultrasonic welding of thermoplastics which produces highest weld strength for complex use in the above said applications is carried out. Also, the possibilities of welding dissimilar plastics are also tested. Tensile testing of above welded samples fabricated through injection moulding was carried out for all possible welds and the ultimate tensile strength was calculated in each case. Of all the welded specimens, at given parameters like weld time, weld pressure and energy director, it is observed that ultimate tensile strength of ABS (8.89 N/mm2) is highest.

The present world persists with a twin crisis of energy consumption and the environmental degradation. Finding a compromise between them provides a breakthrough in the research in energy containments of the engine attachments. Oil pump has role of providing the transmission of oil to other engine parts and acts as the coolant for the moving parts. Conventional oil pump with pressure relief valve is its loss lot of energy in oil re-circulation due to the discharge effect. On contrary, the variable displacement oil pump has an effect on reduction of oil pressure using eccentric ring without having any compromise with the energy consumption. This paper proposes model and experimental methodology of a variable displacement Gerotor oil pump for lubricating the internal combustion engine. This particular unit is performed extremely in terms of rotational speed, delivery pressure and displacement variation.

In additive manufacturing, lasercusing is the selective laser melting technique. Finely pulverized metal is melted using a high-energy fibre laser, by Island principle strategy produces mechanically and thermally stable metallic components with reduced thermal gradients, stresses & at high precision. Maraging steel 300 (18Ni-300) is an iron-nickel steel alloy often used in applications requires high fracture toughness and strength. It maintains dimensional changes at a minimal level, e.g. aircraft and aerospace industries for rocket motor castings and landing gear or tooling applications. Current research attempts to analyze the effect of laser shock peening on lasercused material. Surface roughness of the material was found to be increased by 8%, due to effect of laser shock pulse & ablative nature. Also 8% increase in macro hardness on the surface.

The present research deals with study of pongamia oil methyl ester as a lubricant by blending with anti-wear additive ZDDP. The experimental work carried in this work aims to investigates the friction and wear characteristics by blending zinc diakyldithio phosphates (ZDDP) with pongamia oil methyl ester as lubricant under various loading conditions and temperatures. The coefficient of friction and wear scar depth were determined using pongamia biodiesel blended with 0.3%, 0.6% and 1 % ZDDP by concentration through high frequency reciprocating wear testing machine for 2 h duration. The reciprocating wear tests were performed on an engine liner-piston ring contact under the loads of 40 N, 60 N and 80 N for 2 h duration at temperatures of 100°C, 125°C 150° C with 10 Hz oscillation frequency. The addition of ZDDP with pongamia biodiesel showed marginal reduction in friction coefficient and wear scar depth under all loads and temperatures.