The introduction of gasoline direct injection (GDI) fuel systems has created numerous technical and manufacturing challenges for fuel system engineers. Direct injection systems run at significantly higher pressures compared to port fuel injection, leading to increased stresses on fuel system components. The demands of GDI pump applications have led to significant innovation opportunities in areas such as high-pressure sealing, control of pumping noise and management of increased loads on pumping elements and pump structure. Shifts in the methodologies for the design of components and materials used, as well as changes to the validation and manufacturing processes, have been required to develop fuel systems for direct injection engines.
New technologies for the assembly and joining of materials have also been important to further optimize designs for size, weight, and cost. Recent advances in materials and forming technologies have opened design possibilities to integrate pump sub-systems for improved function and packaging. Of these technologies, laser welding, metal injection molding, and precision stamping are key aids in creating robust, cost-effective and low-weight solutions.
Additionally, the control of debris generation and migration during all stages of the value stream is a critical enabler of pump performance consistency and quality. Part transport, handling and cleaning, audit and analysis considerations must be fully integrated into process layout and material flows to achieve target requirements. Control of environmental air quality and airborne aerosols also plays a critical role in assembly quality.
In this paper, design strategies, production methodologies and key lessons learned are reviewed for current and upcoming Stanadyne GDI pump technology.