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In Automotive, Steel wheels are exponentially replaced by Aluminum wheels because of its feather light, agile performance and better acceleration. One such widely used size is 11.75 x 22.5 wheels for trucks and trailer segment. During the design stage of 11.75 x 22.5 wheel, the valve hole was placed away from the stress concentration zone to reduce the stress on the holes and also the design was validated through all conventional wheel rim testing methodologies (Like CFT, RFT and Bi-axial) and the wheel passed all the test requirements. During the field trials, failures were observed on the valve holes, despite of this hole was away from stress concentration region. Understood from the field trials that, the regular testing was not able to simulate the real field conditions for this particular size and changed the boundary condition in our FEA to simulate the actual conditions. After changing the boundary conditions, we could able to observe more stress in valve hole.

Overheating in commercial vehicles, even though if it’s in LCV segment, is a problem of high significance. There could be various level of problems that may arise due to heat generation resulting from braking (oversized brake drums left the wheels with lesser packaging clearances for air flow and cooling) and some of them are: 1. Early tire wear /reduction in tire life, 2. Air valve heat damage /air leak issues, 3. Frequent puncture problems, 4. Failure of other mating components and other heat initiated failures. However optimum the vent hole shape in a wheel may be, the air flow in the vicinity of drum periphery and wheel rim ID wouldn’t be sufficient enough because of the lesser clearance and packaging space as mentioned earlier. The basic construction of a wheel with disc welded to rim base ID was apparently modified to integrate the disc and gutter and weld it to rim OD.

A “WHEEL” is one of those auto component in a vehicle which necessitates equal attention from safety, ergonomics and aesthetic perspectives. A conventional tube type wheel for commercial vehicles is made of steel with steel side rings (multi-piece construction). In course as headway in wheel design the single piece wheels were developed which used the tubeless tires. These wheels were made available in both steel and aluminum versions. Wherein the aluminum wheels were lighter in weight than steel, aesthetically more appealing and had other significant advantages. Despite the advantages of these tubeless tire wheels, the end user had to invest for both wheels and tubeless tires to replace conventional tube type steel wheels. The retro-fitment calls for higher exchange cost of wheel and tire and this process stands to be more capitalistic to the end user wherein the payback period was longer.

The objective of this project is to reduce the weight of a wheel without affecting its primary functions such as fitment, air flow and fatigue life, the design is made with the concept of variable thickness, meaning reducing thickness wherever the stresses are low and also addressing the failures in the field. However, requirement of a prototype makes the validation process laborious, costly and time consuming. Finite Element Method (FEM) has evolved as a resourceful tool for analyzing various components under a variety of operating conditions. It is being used not only to predict the critical points bearing the highest stress in a wheel, but also to predict its fatigue life. The present study focuses on the design of variable thickness disc and validation of the same using FEM for air flow analysis and Rig testing. The analysis was carried out on existing and proposed designs and the salient features were compared.