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Tractors primarily serve agricultural functions but are also employed in various other applications such as loading, construction, and hauling. Tractors comprise several key assembly, including the engine, transmission, front hood assembly, and skid, among others. The hood is a critical assembly of the tractor, enclosing the engine and its associated parts. It is constructed from sheet metal with a 'Class A' surface finish for aesthetic purposes. The Hood is locked using latch mechanism mounted on the tractor chassis. The primary function of the hood is to facilitate the opening and closing of the hood assembly during servicing, and it often undergoes rough handling. Therefore, it becomes imperative to validate the durability of the hood assembly to ensure it can withstand the real-world conditions it encounters during these operations.

Construction equipment off highway vehicles are heavy industry vehicles that run on diesel engines. To meet the emission norms, these engines have the Exhaust After Treatment System (EATS) which includes two primary subassemblies, i.e., a Diesel Oxidation Catalyst (DOC) subassembly to reduce the HC and CO emissions and a Selective catalytic Reduction (SCR) subassembly to reduce NOx emissions. Because of the excessive vibrations in the engine and continuous heavy-duty usage of the Construction equipment, any failures in the EATS system leading to escape of exhaust gas is a statuary non-compliance. Hence, understanding the effect of engine vibrations and proposing a cost-effective solution is paramount in designing the EATS system including the SCR assembly. A field-testing failure of an SCR assembly has been taken in consideration for this study.

The commercial vehicles market is dominated by manual transmission, due to lower ownership cost. Generally, commercial vehicles are used in large numbers by the fleet owners. The transmission endurance life is very important to a vehicle owner. On the other hand, driver fatigue can be reduced with a smooth gear change process. The gear change process in a manual transmission is carried out with the help of the synchronizer pack. The crucial function of a synchronizer pack in an automotive transmission is to match the speed of the target gear for smooth gear shifting. In a transmission, the loose and the weakest part is the synchronizer ring. The failure of the synchronizer affects smooth gear shifting and it also affects the endurance life of the transmission. The synchronizer ring can fail due to poor structural strength, synchronizer liner wear, synchronizer liner burning, etc.

Vibrational fatigue is a metal fatigue caused by the forced vibrations which are purely random in nature. The phenomenon is predominantly important for the components/systems which are subjected to extreme vibration during its operation. In a vehicle, an engine is the main source of vibration. The vibrational fatigue, therefore, plays a key role in the deterioration of engine mounted components. Multiple test standards and methodologies are available for validating engine mounted parts of an automobile. These might not be appropriate in the case of an off- road vehicle as the vibrational exposure of engine mounted components of an off-road vehicle is entirely different. In the case of an off-road vehicle, the engine mounted components are subjected to a comparatively higher level of vibration for a longer duration of time as compared to the passenger cars.

The increasingly stringent emission legislations provide a continuous challenge for the non-road market. In parallel to transient test cycles, increased emission durability as well as real driving emissions must be fulfilled. The enormous diversification of engines within the different power classes as well as the specific operation requirements regarding various duty cycles, robustness and durability, requires specific solutions to meet these legal limits. The publication shows a cost efficient, reliable and durable approach based on the example of a tractor engine jointly developed by Mahindra & Mahindra Ltd. (M&M) and AVL. It was found that a naturally aspirated (NA) application equipped with common rail and combined with cooled exhaust gas recirculation (EGR) is able to fulfill all legal Environmental Protection Agency (EPA) Tier 4 requirements with a minimum effort on the exhaust aftertreatment side by using only a diesel oxidation catalyst.

Brazil has implemented a new emission regulation for Light commercial vehicles named PROCONVE L6. This regulation follows Environmental Protection Act (EPA) driving cycle; FTP75. This cycle simulates an urban route of 12.07 km with frequent stops. The maximum speed is 91.2 km/h and the average speed is 31.5 km/h. The regulation has proposed that the gear shift pattern of the manual transmission vehicle can be varied according to the manufacturer's specification. This has lead to the strategy of optimizing gear shift pattern without compromising diesel combustion and engine-out emission with optimized exhaust-gas treatment-devices. The emission is demonstrated to Brazilan Authorities with good margins.