Wheel Half-Hub cup assembly interference is among the heaviest found in aircraft engineering, so it is no wonder that it needs extra attention to dismantle. The difference between aluminium and steel coefficients of expansion rates helps, but to raise the hub temperature is an inconvenience and increases the cost of removal. If subsequent inspection or repair work is needed then the component must be allowed to cool before proceeding.
Solution:The portable Half-Hub handling machine can remove cups cold, without damage, and is usually a one man operation. Installation is the reverse procedure in accordance with manufacturer’s instructions, the hub must be heated and the cup chilled to briefly render a non interference condition. If the operation is cup change only, the time taken to remove and reinstall is two minutes, exclusive of heating or chilling time.
Hanley Smith – Solving aircraft maintenance issues
