It is necessary to optimize the process of assembly the stator into the casing of an electric motor. The purpose is to determine ideal parameters of indentation, and the shortest time possible of heating using an induction loop where the stator and casing are not compromised during the procedure.
First we functionally analysed the interference fit i.e. press fit. We wanted to check if the tolerances on the engineering drawings were chosen correctly. We determined the optimal ISO standard fit Ø85 H8/u8, which is very similar to the one already stipulated.
Before we started with the practical tests, we implemented an incoming inspection of the stators and casings, thus preventing inadequate tests of assembled interference fits. This was followed by practical assembly tests, where we determined the ideal parameters of heating by observing the force of indentation of the stator into the casings. These parameters are: current flowing in the loop wire 300.3 A; frequency 170 kHz; and time of heating 18 s. Using these parameters we attained the desired results, where we did not exceed the tolerance of the force of assembly. The casings' temperatures that we reached are between 151ºC and 153ºC.
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