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Highway transportation using truck is an important transport mode of goods and product to their destination. Commercial vehicle is expensive mode of transportation so it will be protected from failure. For Heavy duty truck they are fully loaded at one side of transportation and other side empty transportation. In such case lift axle grounded when truck is loaded and when truck is empty it is in lift condition. Lift axle is play important role while loading so it is important that it should not fail. Many times lift axle fails at weld location due several load come on the axle. In this paper study of weld failure to vertical, braking and lateral load come on lift axle when truck is in loading condition. Weld failure check in CAE analysis with various load cases and compare with actual physical vehicle failure. Weld failure correlation well correlate when actual loading are consider in analysis. For analysis loading data is measure from RLDA data that will be used for analysis.

Virtual validation of automobile components poses a huge challenge and needs continuous process improvements. One of such challenge in FE modelling of welds and understanding its behavior with respect to physical behavior. With the ongoing development of BSVI line of products in commercial vehicle industry, the virtual validation needs to be accurate and close to the physical behavior of the components. The learning and challenges faced during the previous development is implemented in the current study for weld simulation and correlation activity. The brackets welded to the power train components is taken as a challenge in the present work. Initially weld model was depicted in the CAD and was analyzed in CAE by providing proper FE connection. This practice had lot of flaws, approximations due to perpendicularity and flatness concerns in the models leading to consuming a lot of time in model preparation.

The main driving force behind recent innovations in automotive sector is the need to decrease the dependability on fossil fuels and move towards alternative sources for energy. While there is still substantial scope for improvement in conventional diesel and petrol engine based powertrains, the inherent dependency on limited and rapidly depleting carbon based fuels make their long term usage impractical highlighting the need for alternative non-conventional powertrain setups. In the recent past, electric powertrains have come out as favorable alternative as they are extremely flexible in adopting to scenarios where energy for use might be drawn from multiple sources such as solar power, hydroelectric, nuclear reaction, etc. The advantages can further be magnified by adopting the electric power based powertrains in mass transportation application such as bus application.

Brake drum in commercial vehicles is very important aggregate contributing towards major weight in brake system module. The main function of brake drum is to dissipate kinetic energy of vehicle into thermal energy, as a results in braking operation major load comes on brake drum. Hence this is very critical component for vehicle safety and stability [1]. Objective of this paper is to increase the pay load, which is utmost important parameter for commercial vehicle end customers. To achieve the light weighing target, alternate materials such as Spheroidal graphite iron (SGI) has been evaluated for development of brake drum. Many critical parameters in terms of reliability, safety and durability, thickness of hub, wheel loading, heat generation on drum, manufacturing and assembly process are taken into consideration. The sensitivity of these parameters is studied for optimum design, could be chosen complying each other’s values.

The planetary gear system is a critical component in speed reduction of gear system. It consists of a ring gear, set of planetary gears, a sun gear and a carrier. It is mainly used in high speed reduction transmission. More speed variation can be achieved using this system with same number of gears. This speed reduction is based on the number of teeth in each gear. The size of new system is compact. A theoretical calculation is performed at concept level to get the desired reduction of speed. Then the planetary gear system is simulated using ANSYS software for new development transmission system. The final validation is done with the testing of physical parts. This concept is implemented in 9speed transmission system. Similar concept is in development for the hub reduction with planetary gears. The maximum 3.67 reduction is achieved with planetary system. The stresses in each pin is calculated using FEA.

A propeller shaft is a mechanical component of drive train that connects transmission to drive wheels/axle with the goal to transfer rotation and torque. It is used when the direct connection between transmission and drive axle is not possible due to large distance between their respective assigned design spaces. In commercial vehicles especially in heavy duty (GVW/GCW>15 tons) a single piece propeller shaft is seldom used due to its inherent disadvantages and therefore, most if not all, of the setups consists of multiple pieces of propeller shaft which are directly mounted on to frame cross members with the help of mounting brackets. As such the mounting bracket assembly undergoes various dynamic and static loading conditions and should be able to withstand these loads. This paper will focus on the FEA analysis of propeller shaft mounting assembly system. Furthermore, these results will be correlated with physical tests results collected from test rig and physical vehicle testing.

To compete with the current market trends there is always a need to arrive at a cost effective and light weight designs. For commercial vehicles, an attempt is made to decrease weight of the current design without compromising its strength & stiffness, considering/bearing all the worst road/engine load cases and severe environmental conditions. The topic was chosen because of interest in higher payloads, lower weight, and higher efficiency. Automotive cylinder head must be lighter in weight, to meet increasingly demanding customer requirements. The design approach for cylinder head has made it difficult to achieve this target. A designer might make some judgment as to where ribs are required to provide stiffness, but this is based on engineering experience and Finite Element Analysis (FEA) of the stand-alone head.

The existing head cover is having external oil and blow by separation unit, which is not only costlier but also complex and leads to increase in overall height of engine which was difficult to integrate in new variants of vehicles. A new head cover has been designed with internal baffle type oil and blow by separation system to ensure efficient separation and proper packaging of the system in new variants. The new system has been finalized after 26 DOE’s of different wire mesh sizes and different baffle plate size and positions. The final system has two bowl shaped separation unit with wire mesh, two cup type oil separation passages and one baffle plate for separating blow by. The system works on condensation and gravity method. The blow by is guided through a well-defined passage integrated in aluminum cylinder head cover itself. The passage angle is maintained to ensure minimum oil flow with blow by.

Three on the tree, four on the floor. The gear change mechanism is a component that is too often taken for granted but it is one of the more important features of the vehicle. It must be quick and smooth in action, efficient and totally reliable. Modern driving conditions demand that the driver makes frequent gear changes and a mechanism that is temperamental or inaccurate can be both frustrating and dangerous as well as physically tiring. The gear changing mechanism starts, quite obviously, with the gear lever. Most stem from the fact that a gear lever must move in two planes, forward and back and then from side to side to move across the gear "gate". A good many drivers think of gear changing as one simple action. This is more a tribute to the design of gear changing mechanisms than a reality. There are multiple gear selector mechanisms that are available for use in commercial vehicle industry.

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.

Advanced Non-linear topology optimization methods have been addressed as the most promising techniques for light weight and performance design of Powertrain structures. The theoretical achievements are obtained both mechanically and mathematically. Nowadays, the great challenge lies in solving more complicated engineering design problems with multidisciplinary objectives or complex structural systems. The purpose of this paper is to provide a forum to present new developments in structural Non-linear topology optimization. The advantage of the proposed method is that structural optimization on irregular design domains can be carried out easily. Furthermore, this method integrates the stress analysis and the boundary evolution within the framework of finite element methods. In this paper, mainly focused on the Commercial Vehicles Powertrain component i.e. Transmission Housing.

To compete with the current market trends there is always a need to arrive at a cost effective and light weight designs. For Commercial Vehicles, an attempt is made to replace existing Gear Shift Fork from FC Iron (Ferro Cast Iron) to ADC (Aluminum Die Casting) without compromising its strength & stiffness, considering/bearing all the worst road load cases and severe environmental conditions. ADC has good mechanical and thermal properties compared to FC Iron. Feasible design has been Optimized within the given design space with an extra supporting pad for load distribution. Optimization, Stiffness, Contact pattern has been done using OptiStruct, Nastran & Ansys for CAE evaluation. A 6-speed manual transmission is used as an example to illustrate the simulation and validation of the optimized design. Advanced linear topology optimization methods have been addressed as the most promising techniques for light weighting and performance design of Powertrain structures.

Proper sealing of an engine is very important parameter in an engine design. Even small amount of gas leakage from the engine can affect the overall performance of the engine during operation. There are two important factors in enhancing the efficiency of the sealing of the gasket are right tightening torque of bolts & gasket design. In this study, both the distribution of the contact pressure on the gasket, and the stresses of the cylinder head at different loading conditions, such as cold assembly, hot assembly, cold start, and hot firing, is simulated by commercial tool, based on the finite element method (FEM). The results shows that the efficiency of the sealing of the cylinder head gasket depends on the tightening torque of the hold-down bolts, without taking into consideration any thermal load resulting from the temperature distribution in the cylinder head.