Regulatory Norms and Effect on Transmission Component Validation

With the advent of BS VI regulations, automotive manufacturers are required to innovate the powertrains, fuel systems, exhaust and its after treatment systems to meet the regulatory requirements. The exhaust regulations can be met either by reducing the exhaust gases being generated by the engine (attacking the source) or by treating the exhaust gases in after treatment devices. The choice of the opted system varies with the manufacturer. The after-treatment devices such as catalytic converters are generally mounted in the engine compartment to take advantage of high temperature of exhaust gases to yield the reactions. Such an arrangement imposes a lot of thermal load on the peripheral components such as gearshift cables, bearings, oil seals, driveshafts etc. Thermal shields or thermal sleeve are used to address thermal issue and to protect transmission components. System level validation test requirement of transmission need to be re-visited considering change in environmental condition of operation. Also, component level test related to thermal sleeve and thermal shield need to be included in the component level validation plan. This paper discuss different validation requirement derived to validate the thermal sleeve and thermal shield from performance and durability point of view at system level and component level. Effect of parameters such as air gap, rotational speed (for component such as driveshaft), temperature of source, air draft, presence of dust and dirt in the operating environment etc for the derivation of test criteria are also discussed in detail. This paper also explains the test setup requirements for the thermal data acquisition during validation test. Proposed validation process help to get early feedback during the development and reduce the overall development time by avoiding requirement of complete validation of affected aggregates at vehicle level.