In the current scenario of increasing fuel prices and global warming, there is need to redesign and evaluate existing power train & valve train to be more efficient. Many initiatives were taken & one such change is to go for assembled camshaft. Major challenges are anchoring of cam lobes, bearings & spigot with tube. It is accomplished with the application of internal pressure by hydro forming machines. The main consideration for the use of an assembled camshaft is that there should be no deterioration in the bending and torsional stiffness and hence the valvetrain performance. Another challenge is to optimize material & process to maximize productivity & minimize cost. This paper presents the systematic approach towards design & development of assembled camshaft. It includes analysis results comparing the valve train performance for key parameters like camshaft deflection, valve train natural frequency, cam and tappet contact stresses, valve jump, valve bounce phenomenon, spring surge characteristics etc. Also the camshaft is analyzed for durability. It includes methodology to develop & test assembled camshaft. Major benefits are improved valve train performance due to reduced rotational inertia, lower NVH and reduced power required to drive the valve train. Also cost is low comparatively. This new design satisfies static test & covered substantial hours of durability test.
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