Rapid jacking method for online rotor extraction of large motors

Abstract

The invention relates to the field of maintenance of steel equipment, in particular to a quick lifting method for online drawing a rotor of a large motor. The quick lifting method comprises the steps as follows: dismantling a cardan shaft of the motor; dismantling an upper tile of a bearing base of the motor, an outer cover of the motor and a foundation bolt of a stator of the motor; dismantling an encoder of the motor and a thrust bearing. The quick lifting method is characterized in that a lifting beam of the rotor is lifted by a traveling crane and arranged at the top of the stator of the motor; chain blocks and steel cables are hung at the two ends of the lifting beam of the rotor; the rotor of the motor is lifted through the chain blocks, and is not contacted with the interior of the stator of the motor; electric hydraulic jacks are erected at the four corners of the stator of the motor and used for synchronously lifting the stator of the motor and the rotor, fixed through the lifting beam of the rotor, of the motor; when the electric hydraulic jacks are lifted to the lowest position of the rotor of the motor beyond the plane of the bearing base, the lifting beam of the rotor is lifted by the traveling crane, and the rotor of the motor is drawn out. The quick lifting method can quickly and safely lift the large motor and finish the rotor drawing operation, and overcomes the defects in the traditional large motor lifting operation.

Description

technical field [0001] The invention relates to the field of steel rolling equipment maintenance, in particular to a rapid jacking method for a large-scale electric motor to extract a rotor online. Background technique [0002] In the current metallurgical enterprises, the online rotor extraction of large motors generally adopts the method of motor jacking - pumping the rotor. The jacking method is based on the fact that the rated lifting capacity of the driving in the workshop where the main motor of the rolling mill is located is generally less than the total weight of the motor, which cannot be lifted with one hook. The rotor and the stator of the motor, therefore, the rotor and the stator must be used as separate components, and at the same time, the crane and the jack are used to realize the principle of multiple alternate lifting. The general idea of ​​this method is to use the crane to hang the motor rotor, use mechanical jacks evenly distributed on the four feet of t...

AI Technical Summary

Problems solved by technology

[0003] The above-mentioned motor jacking-pulling rotor method mainly has the following problems: 1. The air gap value between the motor rotor and the stator is generally very small. Taking the 7000KW synchronous motor manufactured by Shanghai Electric Machinery Group as an example, the air gap value is only 15mm. It can be seen that the maximum lifting height of the motor cannot exceed 30mm each time. According to the calculation of the total lifting height of 900mm, a total of 900mm÷30mm / time=30 times can be used to push the motor to the position of the pumping rotor. The number of lifting times is long and the time is long; 2. Each jacking needs to be realized through synchronous and alternate cooperation between the driving and the mechanical jack. The mechanical jack is operated manually, and the synchronization is difficult to ensure. A slight deviation will cause the rotor to collide with the stator, and the risk of scratching is high; 3. In the above method, a mechanical jack must be used, and it must not be replaced by a hydraulic jack, because once the hydraulic jack leaks or is out of sync, the stator and the rotor will contact, causing all the weight to act on the driving, and it is very likely that the lifting capacity of the driving will exceed the limit. Safety accidents; 4. The mechanical jack lifts the stator manually, which is inefficient, long construction period and high cost

Images