My thesis project is the result of a six-month internship in FPT Industrial, the acronym for Fiat Powertrain Technologies. The company is responding to the increasingly restrictive regulations in terms of pollution with the opening of the E-powertrain Plant, the first carbon-neutral plant in Italy, where a high-performance electric motor is being produced for a Sport car model that is going to be released on the market. Since this electric motor has to meet very high-quality standards and is completely new, the Plant Quality team, with whom I have collaborated in developing this analysis, has decided to adopt the Production Part Approval Process (PPAP), commonly used to prove the conformity of components supplied by external suppliers, also to the gears that are produced in-house in another area of the Production Plant, the Gearbox Area, and that form the gearbox system of the electric motor.