As India has decided to move to BS VI emission regulation by 2020, all original equipment manufacturers (OEM) and Tier 1 suppliers are working towards achieving the goal. Overall reduction in CO2 reduction can be achieved through power to weight reduction of various power train components. In a conventional Multi Point Fuel Injection (MPFI) engine, a fuel rail or delivery pipe is mounted on the intake manifold or cylinder head, which delivers fuel to inlet port at a fuel pressure of 350 kPa to 400 kPa through fuel injectors.
In today’s automotive industry most of the fuel rail components are made through PDC process of aluminium because of its ease of availability and machinability. Therefore, several studies have focused on alternate materials like sheet metal and plastic by reducing the weight of the fuel rail. Sheet metal fuel rails can also be made with significant weight reduction. However, their manufacturing processes are complex. However, with plastic fuel rail, it can naturally dampen the fuel pressure fluctuations. Hence, a separate pressure pulsation dampener is not required as in the case of aluminium material fuel rail.
In this work, a detailed study is done with plastic fuel rail concept. For proper sealing to withstand high fuel pressures, different joint types and energy directors are studied and evaluated to arrive at optimum design. The final sealing thus arrived can withstand a burst pressure of 2000 kPa. Finally, this study has resulted in reduction of weight by 2/3rd and cost by 50% meeting the performance and durability test requirements.
