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Flex Connectors are intended for mitigating the relative movement of exhaust system components along the axis of the system arising from the thermal expansion due to intermittent engine operation. Flex connectors must not be installed in locations, where they will be subjected to destructive vibration. Hence, the stiffness of the flex connector plays an important role, while designing or selecting the right design. It consists of a multi-ply bellows combined with an inside and an outside steel braid. The liner is included to reduce the temperature of the bellows and improve flow conditions. The braid is included for mechanical protection and to limit the possible extension of the joint. It has only axial translational motion.

Crankshaft is one of the critical components of an engine (5C: cylinder head, connecting rod, crankshaft, camshaft and cylinder block). It is subjected to repetitive and dynamic loads due to cyclic operation of an engine and inertia forces. Due to uneven mass distribution, failure zones occur near fillets and holes in journal locations during operation of the engine. Hence, this topic was chosen because of increasing interest in higher payloads, lower weight, higher efficiency and shorter load cycles in crankshaft equipment. Calculation of Crankshaft strength consists initially in determining the nominal alternating bending and nominal alternating torsional stresses, which multiplied by the appropriate SCF (Stress Concentration Factor), result in an equivalent alternating stress. This equivalent alternating stress is then compared with the fatigue strength of the selected crankshaft material. This comparison will show whether or not the crankshaft concerned is dimensioned adequately.

To compete with the current market trends there is always a need to arrive at a cost effective and light weight designs, hence the need for upgrading the existing/proven integral connecting rod to fracture split connecting rod. This technique provides gains as weight reduction and consequently reducing noise and vibration due to the decrease of the oscillating mass from the system. Using the proposed fracture split connecting rod, it is estimated that cost savings of up to 10%, reduction in weight and better fatigue performance (25% - 30%) can be achieved. For this, we have used simulation tools to reduce number of physical tests and thereby achieving considerable reduction in design and development time and cost. High carbon alloy steel used for manufacturing fracture split connecting rod and it doesn’t require additional heat treatment after hot forging.

Crankshaft is one of the critical components of an engine (5C: cylinder head, connecting rod, crankshaft, camshaft and cylinder block). It is subjected to repetitive and dynamic loads due to cyclic operation of an engine, inertia forces due to uneven mass distribution with failure zones as fillets and holes in journal locations. Fatigue is most common cause in failure of the crankshaft. Its failure will cause serious damage to the engine so its reliability verification must be performed. The load is applied as per the firing order of the cylinder for 2 revolutions of crankshaft, to cover firing condition of each cylinder. Loads with respect to crank angle or time are applied at respective locations and results are taken on 360 steps for 2 complete revolutions of crank. The topic was chosen because of increasing interest in higher payloads, lower weight, higher efficiency and shorter load cycles in crankshaft equipment.

The cabin or cab is an enclosed space where the driver and co-driver are seated. Structural parameters such as modal and stiffness characteristics are of key importance for its durability study and driver’s comfort. The desired strength and stiffness value of the cabin have to be met at the development phase itself. In developing new cabin models numerical simulations are used for estimating vehicle performance to reduce the development cycle. But, the conventional method of modeling the cabin using 2-d elements and performing subsequent iteration steps to arrive at the desired stiffness and strength value will be cumbersome and time consuming. Thus, a methodology of FE modeling of the truck cabin using 1-D elements has been proposed in this paper which will reduce the analysis time of successive iterations. For this purpose an existing proven driver’s cabin is modeled using 1-D elements.