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Attention! Problems with these parts will cause the running 500KW diesel generator set to shake

July 01, 2022
Generally speaking, like 500KW this kind of horsepower, power enough diesel generator in the process of vibration is normal, but sometimes more intense shaking, which is more abnormal, the user should promptly find out the cause and solve, in general, the unit rotating part of the imbalance, mechanical failure and electrical failure are the three main reasons for the unit shaking.
1. Rotating part imbalance
It is mainly caused by the unbalance of rotor, coupler, coupling and transmission wheel (brake wheel).
The treatment method is to find a good balance of the rotor first. If there is a large drive wheel, brake wheel, coupler, coupling, should be separated from the rotor to find a good balance. Then there is the rotating part of the mechanical loosening caused by. Such as: core support loose, oblique key, pin failure loose, rotor tying is not tight will cause the rotating part of the unbalance.
2. mechanical part of the failure
(1) the linkage part of the shaft system is not aligned, the center line does not coincide, the centering is not correct. This kind of failure is mainly caused by poor alignment and improper installation during the installation process. There is another situation, that is, some linkage part of the centerline in the cold state is overlapping consistent, but after a period of operation due to the rotor pivot point, the foundation and other deformation, the centerline is destroyed, and thus generate vibration.
2) The gears and couplings connected with the generator have problems. This failure is mainly manifested as bad gear bite, serious tooth wear, poor lubrication to the wheel, skewed coupling, misalignment, tooth coupling tooth shape, tooth pitch is not right, excessive clearance or wear, will cause a certain vibration.
(3) the generator itself structural defects and installation of the problem. This failure is mainly manifested as journal oval, shaft bending, shaft and shaft tile clearance is too large or too small, bearing seat, foundation plate, a part of the foundation and even the whole generator installation base rigidity is not enough, the generator and the foundation plate is not fixed between, the foot bolt is loose, bearing seat and the foundation plate is loose. The gap between the shaft and the shaft tile is too large or too small not only can cause vibration but also can make the shaft tile lubrication and temperature abnormalities.
3. Failure of the electrical part
Electrical part of the failure is mainly caused by electromagnetic reasons, mainly including: AC diesel generator stator wiring errors, wire-wound asynchronous motor rotor winding short circuit, synchronous diesel generator excitation winding inter-turn short circuit, synchronous diesel generator excitation coil connection error, cage asynchronous motor rotor broken strip, rotor core deformation caused by uneven stator and rotor air gap, resulting in unbalanced air gap flux thus cause vibration.
For the above causes 500KW diesel generator set shaking during operation, the solution to the problem of shaking can be referred to the following.
1, the diesel generator rotor must be proofread dynamic balance, to reach the accuracy of the drawing rules of dynamic balance.
2, according to the drawing rules of the trademark selection of precision qualified bearings. Check the unevenness of the stator and rotor air gap, adjust the device until the unevenness of the uniformity meets the requirements.
3, according to the specified cooperation precision device bearing and rotating shaft and end cover.
4, bearing device prohibit the use of knocking method, the choice of oven heating bearing hot set method.