Technical status of reducer starter
2021-4-13 13:26:59
1. The technical condition of reducer starter plays a decisive role in the normal starting of reducer. Practice has proved that most of the burned reducers are caused by improper starting equipment. If the starter starts without phase, the contactor contact will start the arc.
2. The maintenance of starting equipment is mainly cleaning and fastening. If the contacts of the contactor are not clean, the contact resistance will increase, resulting in thermal contact, phase loss and combustion of the reducer. The core of the contactor suction coil is rusty and covered with dust, which will cause the coil to be loosely sucked in and damaged. High noise will increase coil current and cause coil failure.
3. Check the transmission and rotating parts
Check whether the transmission is flexible. It is reliable; the concentricity of coupling is standard; the flexibility of gear transmission, etc. If blockage is found, stop immediately to find the cause, and then run.
If the pressure reducer is overloaded, the main reason is overload, low voltage or mechanical blockage caused by the driver. If the overload time is too long, the deceleration opportunity will absorb a lot of active power from the grid, the current will increase sharply, and the temperature will rise correspondingly. At high temperature, the insulation of the reducer will age and burn out. Therefore, always keep the reducer running at rated current.
4. Current
When the reducer exceeds the rated current, the coil temperature will rise, resulting in insulation deterioration. Life is shortened or the coil is burnt out, so the load should be made lower than the rated current. In addition, when the phase to phase voltage of the three-phase reducer is unbalanced, the unbalanced current will be generated, and the temperature rise will be unbalanced, resulting in local overheating. Therefore, the current value of each phase should be measured and recorded regularly. For three-phase asynchronous reducer, the difference between the current of one phase of three-phase current and the average current of other two phases shall not exceed 10% to ensure the operation of reducer. If it exceeds, it means that there is a fault in the reducer, which needs to be found and eliminated in time.
5. Insulation resistance test
When the reducer is placed in humid air, when the stop time is long or the ambient temperature changes sharply, the electrical performance will decline due to the hygroscopicity of the insulation layer. In addition, the moisture or adhesion of the insulator to the surface of the insulator will also lead to the increase of the insulation resistance. Therefore, the periodic inspection or disassembly of the equipment and the long-term shutdown of the reducer must be measured in mm before the insulation resistance. When measuring low-voltage voltage reducers, 500 V megohmmeter voltage is usually used, while voltage reducers use 1000 V and above corresponding megohmmeter voltage.
6. Check the reducer temperature
If the reducer is overloaded, the voltage will run for a long time under the rated or unbalanced state. When the temperature rises due to poor ventilation, the insulation will deteriorate and the service life will be shortened.
If the bearing of the reducer is overheated and short of oil, if the temperature near the bearing is found to have risen, it should be stopped immediately. There is no crack, scratch or damage on the surface of bearing roller and raceway, whether the bearing clearance shakes too much, whether the inner ring rotates on the shaft, etc. If the above phenomenon occurs, the bearing must be replaced before reprocessing.
In addition, ventilation should be checked regularly to measure the inlet and outlet temperatures of the cooling air. When the temperature difference is too large
Therefore, it is necessary to check the anchor bolts, reducer end cover, bearing gland, etc. And whether the grounding device is reliable, and find out the problem in time during the operation of the reducer, especially when the power of the reducer is large. Normal vibration can touch the stator frame by hand. Abnormal sound can be used in the ear or listening stick. If you need more information, use a vibrator. If it is different from the daily state, you should check it in detail. Vibration is caused by other mechanical reasons such as poor foundation, unbalanced rotor, abnormal bearing or vibration transmission. There are still electrical reasons, such as electromagnetic force caused by unbalanced power supply voltage and uneven air gap.
