Destoner machine noises

In daily operation, destoner machine may have some noises. How to find out the cause of the noises and how to solve the problem?
First, when the destoner machine wind screen has noises, this always has close relations with the wind screen conformity. Due to the rough point of weld in corn processing, the wind screen small mouth margin height is not consistent. In allocation, it always has friction with the rotor end.
Second, electromagnetism sound: it can be divided into high frequency and low frequency. It may be because of the bad conformance of the axle iron core chute，the rough iron core inner chamber and the inconformity of the rotor outer diameter processing. Usually we can adopt the method of changing rotor to solve this problem.
Third, high and low voice from the motor:
a. The destoner machine stator and rotor have uneven air gap. If the voice is sometimes high and sometimes low, and the voice interval time keeps invariant, then it may be caused by the bearing abrasion which makes the stator and the rotor not concentric.
b. Unbalanced three-phase-current.
c. Loose iron core.
Fourth, if there has uneven crash, it may be caused by the crashing between the fan blade and the fan housing.
Fifth, the noises from the stator and the rotor friction belongs to the limiting condition of chamber sweeping.
Finally, other factors also may cause destoner machine noises, such as slot sedge part popping, vibration, long fixed bolt of the bearing cap. We should check whether the destoner machine each part is loose.
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