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Manufacturing processes often produce a large amount of heat, which needs to be pumped out of the factory to maintain thermal stability and comfort. Thermal comfort is essential to maintain a suitable working environment in a factory. It has a strong impact on the health and productivity of workers. In addition, it is mandatory to keep the working environment within specified thermal and relative humidity ranges. Periodic assessments of these thermal parameters is routine in most factories. Inclusion of additional manufacturing equipment or processes can lead to a significant change in the working environment and consequent comfort, this needs to be addressed quickly. Rather than wait to measure these effects it is preferable to develop a reliable simulation method for the proactive study and improvement of thermal comfort levels. A reliable simulation approach is developed in this study for the prediction of thermal comfort in an automotive manufacturing plant.

During the assembly process of planetary gears, the pinion shaft is initially pressed in to the planetary carrier and then staking is performed to fix the pinion shaft to the carrier. The main purpose of the staking process is to prevent the movement of the pinion shaft during transmission operation. During assembly there should be minimal distortion of the assembly. The press-in process, pinion shaft and carrier are subjected to extremely high frictional loading due to the interference fit. The staking process permanently deforms the pinion shaft top and bottom ends, forming a protrusion that holds the shaft in position. The pinion shaft needs to sustain operational loads exerted by helical planetary gears, which tend to push the carrier flange out of position during operation. Staking length, staking force and interference between shaft and carrier hole are the critical parameters, which determine the maximum axial force that the pinion shaft can withstand.

In the shop floor, cracking issue was noticed during assembly of valve seat and valve guide in the engine cylinder head, especially near the valve seating area. This paper reveals a non- linear finite element methodology to verify the structural integrity of a cylinder head during valve seat and valve guide assembly press-in operation under the maximum material condition, i.e., smallest hole size on cylinder head for valve seat and guide and largest diameter of valve seat and guide. Material and geometrical nonlinearities, and contact are included in this method to replicate the actual seat and guide press-in operation which is being carried out in shop floor. The press-in force required for each valve seat and valve guide assembly is extracted from simulation results to find out the tonnage capacity of pressing machine for cylinder head assembly line. Stress and plastic deformation due to assembly load are the criteria checked against the respective material yield.