(1) the powder selecting machine of vertical roller mill electrical noise: in the powder selecting machine motor in the process of debugging, 5Hz start the motor, the output shaft of the motor end unusually mild metal friction sound, then gradually in motor speed to 30Hz, the slight abnormal sound gradually strengthen (2 meters away from the motor, can hear the sound of metal friction obvious) after shutdown, discuss, analysis of the causes of the abnormal sound, have the following possibilities: a) the end of the motor output shaft bearing lubrication is insufficient; b) the motor output shaft end gland hole and a motor output shaft eccentricity, cause gland and the output shaft friction; C) the output shaft of the motor running deflection jump greatly, cause gland and the output shaft of the friction; d) the output shaft of the motor bearings in the foreign body, friction caused when the bearings work.
In view of the lack of site condition, we can only be for 1, 3 two possibilities for investigation. First, we check the output shaft of the motor through the dial gauge segment diameter and end jump jump, the results showed that there was no problem, ruled out the possibility of 3. After that, we query the motor factory time and standard oil, according to motor manual filling of the lubricating grease, start the motor and gradually speed up to 50Hz operation again, from just started when the slight metal friction sound appeared later disappeared completely after operation, and no longer appear.
Process in the grease added after investigation of abnormal sound operation, produce abnormal sound of motor magnetic disorder caused by the regular, in this case we analyze the reasons are as follows: (1) site voltage instability; (2) had abnormal load affects the dynamic balance of the motor output shaft; (3 interference of frequency converter) near; (4) the frequency converter set error or abnormal operation.
In view of the above causes, we gradually investigation, the ultimate reason identified as motor manufacturers with the output shaft and half shaft coupling fastening gland eccentric, causing the motor output shaft of dynamic balance is affected, produce abnormal sound.
(2) the powder selecting machine of vertical roller mill could not start: after frequency conversion motor and reducer to confirm normal, began to prepare to drive the rotation of the rotor powder selecting machine, motor starting at a frequency of 5Hz, the rotor does not start running. In view of this phenomenon, we carried out a careful analysis of the powder selecting machine of vertical roller mill parts of the structure, that there are several possibilities: a) selected internal rotary powder machine part of the bearing group running interference or bearing hold; b) powder selecting machine rotor parts and related structural interference or death card; c) classifier rotor axis Perpendicularity Error of installation too high, resulting in radial load increasing; d) V with the preload is too large, resulting in load aggravate; E) selecting packing powder machine seal extrusion, friction resistance increases, causing load aggravate.