Transcend Transmission Assy

Finecast Foundry Ltd have developed a gearbox consisting of 5 main castings and fragile internal cores printed using cerabead to offer a more robust solution

Component

Gearbox assembly for the automotive sector, in A356 aluminium alloy, consisting of five main castings, each with very high dimensional tolerances.

Challenges

  • Complex internal core geometry, with risks of gas being trapped during casting and core cracking.
  • High internal core dimensional accuracy required.
  • High casting integrity requirements.
  • X-ray inspection: AMS STD 2175 Class 1 Grade C.
  • Casting to resist leak testing confirmed by pressure testing to 20 Bar.

Method

  • Close collaboration with customer to optimise design for casting with additional bosses to provide core support.
  • Casting simulation used to confirm filling geometry, reduce liquid metal turbulence and optimise methoding design to reduce risk of shrinkage porosity.
  • Chemically bonded sand casting used to produce casting mould.
  • Cerabead cores used to reduce risk of core cracking during casting and optimise dimensional control.
  • Cores design with small vents to reduce risk of gas entrainment.
  • 3D printed cores to increase strength and steel guide pins employed to minimise assembly variability.
  • GOM scanning of mould and core assembly prior to casting to ensure mould accuracy.
  • HIPping of casting completed prior to pressure testing to 20 bar.
  • Visual and full NDT inspection to ensure customer specification achieved.