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Mobile WebSiteAs the scale of modern industrial production of carbon black increases, the production equipment is increasingly large and the power of the motor is also getting bigger and bigger.
First, the bearing problem
In the larger pump motor and more use of sliding bearing structure. In a few years of use, we feel that the sliding bearing structure, although beneficial, but in the use and maintenance than rolling bearings to trouble, especially in the long production run case, the sliding bearing to often add thin oil , But also grinding the bearing regularly, but also to control the installation of the gap pad, poor handling will appear oil leakage, oil spills and other issues. The rolling bearing grease on a regular basis as long as the grease can be added, problems only need to be replaced, the maintenance workload is small.
Second, the motor cooling problem
Large high-voltage motors are designed with cooling devices, water cooling, air cooling devices, etc., the cooling device is the heat exchanger, the water cooler motor are generally placed on top of the motor, the cooling water contains impurities, Cooler heat exchange capillary will produce fouling plug the capillary, affecting the cooling effect of the motor, chemical cleaning agent cleaning scale, the capillary will be corrosive, so after cleaning must be checked to confirm no leakage. If the cooling water into the motor to damage the insulation, will cause a short circuit between the motor burned accident. The wind cooling motor in the operation and maintenance process, the cooling fan blades will be deformed, resulting in vibration and damage caused during operation of the motor, it must be noted. Air cooler overhaul must pay attention to the inner and outer wall cooling pipe cleaning, especially the summer hot weather, can effectively avoid the motor temperature is too high and forced to reduce the output to affect the production efficiency.
Third, insulation problems and handling
In accordance with operating procedures, large high-voltage motor shutdown for some time, before starting the boot must check the dielectric strength, the general use of shake table (also known as megger) inspection, the use of voltage levels above 500V 1000V shake table, F insulation class 6000V above the use of voltage levels 2500V shake table, insulation good motor insulation values are generally in the hundreds of megohms above, 10KV motor insulation strength in cold state can be 1M∥1KV to control, if found below this value, Check the following.
(1) Check the stator coil lead porcelain bottle first. If the porcelain bottle is too dirty, there will be enamel and the defect will flash over the arc of the shell. It may be that the insulation caused by this problem is reduced and the porcelain bottle can be replaced.
(2) The stator coil leads are generally fixed to the inner leg of the motor case. Damage to the insulation layer due to vibration, aging and other factors during the long-term use of the insulation of the lead wire can reduce the dielectric strength and even short-circuit the case , Inspection must unpack the banding to see if there is a defect, find out the point of insulation damage, and then wrapped with insulating material, and then coated with insulating paint drying, with a shake table to test the insulation value can be qualified run.
Fourth, the rotor and slip ring problems
Rotor is a rotating movement, high-voltage wound motor rotor, slip ring and leads appear more insulation failure, although the rotor relative to the stator, the voltage is much lower, but the current is much higher than the stator, so The probability of failure will be higher, in the use of moisture resistance, insulation material level, there will be hidden problems if the quality of the problem. Common due to rotor lead is not fixed firmly, resulting in insulation bandage loosening, insulation material in the rotor rotation process to short to ground; isolation ring between the three phases isolated bushing due to wear and tear caused by the phase short circuit. Some problems are only exposed when the motor is started, and the rotor in the stator, it is difficult to directly check, and sometimes must be its core-pulling can be found, but you can determine the fault according to the phenomenon of reprocessing, through certain means try not to disintegrate Solve the problem.
