Transmission shaft development - inner and outer shaft

Be ingenious

Customer: Tier 1 supplier to the automotive industry

Market: Light duty on highway - Asia

BRACE execution: Powertrain domain cluster

Location: BRACE Offices and Customer site

For use in a transmission a shaft was developped consisting of an inner and an outer shaft. The goal of the development was to operate the two shafts at different speeds. Also different oil pressures needed to be maintained in between the shafts. Major difficulties existed in maintaining a capable manufacturability and assembly process.

Different concepts were generated (using CAD, FEA, general flow/ pressure/ strength -calculations). In cooperation with a team at the client containing development, project, manufacturing and process engineers, 2 concepts were chosen. Both concepts were prototyped to review process capability and design feasibility and functionality.

  • Manufacturing trial run on internal shaft operations
    • rolling (at customer’s factory)
    • reaming (at customer’s factory)
  • Trial run on heat treatment process and deviations
  • Manufacturing trial run on internal shaft operations after hardening
    • grinding (at customer’s factory and external partner)
    • honing
  • Dynamic seal ring prototypes (from customers supplier)
  • Various tests at customers site;
    • Prototype transmission build to asses difficulties in assembly
    • Test bench functional concept tests
    • Test bench leakage tests
    • Endurance test

After validation one of the concepts was chosen that fitted best in the customers process.