WESTINGHOUSE Three Phase Induction Motors

When there is slight abnormal noise or vibration in the motor, immediately investigate the cause (such as loose coupling, uneven belt tension, lack of bearing grease), prohibit operation with faults, and prevent the fault from expanding.

Core maintenance and upkeep system

（1） Maintenance cycle and core projects

Maintenance cycle, maintenance level, core project operation points

Daily inspection of oil level, leakage monitoring, and visual inspection. The sliding bearing oil level is at the center of the oil gauge and there is no dripping; There is no dust accumulation on the surface of the motor, and the fan is running normally

Weekly routine inspection of bolt tightening, coupling status, current monitoring anchor bolts, coupling bolts, and junction box bolts for no looseness; Three phase current balance, no abnormal fluctuations

Monthly focus on checking filter cleanliness, belt tension adjustment, vibration detection, cleaning of bearing lubricating oil filters, and cooling fan filters; Adjust the belt tension and replace the aging belt; Vibration value ≤ 3.8mm/s

Quarterly intermediate maintenance insulation resistance testing, bearing grease repair, winding cleaning insulation resistance ≥ 5M Ω; grease repair according to bearing model (such as 6310 bearing with 40g, 22218 bearing with 120g); Compressed air (≤ 4kg/cm ²) to clean the dust on the surface of the winding

Every six months, advanced maintenance oil replacement, end cover sealing inspection, heater calibration, sliding bearing replacement, rust and oxidation suppression turbine oil (ISO VG32/VG68); Check the sealing ring of the end cap and replace it if it ages; Verify the working status of the heater

Annual in-depth maintenance of vibration analysis, re alignment of couplings, and evaluation of winding insulation professional instruments for vibration spectrum analysis to identify potential faults; Re check the coaxiality of the coupling, and adjust if the deviation exceeds the standard; Evaluate the insulation status of the winding and perform drying treatment if necessary

Open the cover every 2 years to check the status of the coil, detect bearing wear, and measure rotor clearance. Open the end cover and inspect the stator coil for discoloration, aging, and looseness; Detect bearing wear (radial clearance ≤ 0.1mm); Measure air gap (uniformity error ≤ 10%)

Disassemble and maintain the rotor guide bar inspection, stator core inspection, and bearing replacement every 4 years. Disassemble the motor and check that there is no looseness or cracking at the welding point between the rotor guide bar and the end ring; Check whether the stator core is corroded or deformed; Replace the rolling bearings and re grind the sliding bearings

（2） Core component maintenance details

1. Winding maintenance

Cleaning: Use compressed air (pressure ≤ 4kg/cm ²) to blow the dust on the surface of the winding from the inside out. If there is oil stains, wipe them with alcohol or neutral cleaner. Do not use chlorine containing solvents (such as acetone) to avoid corroding the insulation layer.

Insulation testing: Use a 500VDC megohmmeter to measure the insulation resistance of the winding every quarter. Before measurement, disconnect auxiliary equipment such as heaters and temperature detectors, and discharge after measurement; If the insulation resistance is lower than the standard value, use hot air drying (temperature 60-80 ℃, continuous for 24-48 hours) or low-voltage electrification drying (apply 10%~20% of the rated voltage, continuous for 12-24 hours).

Moisture protection: When the motor is idle for more than one month, activate the space heater to maintain the winding temperature 3 ℃ above the dew point; Before restarting after a long-term shutdown, insulation resistance testing must be conducted to meet the standard before starting.

2. Bearing maintenance

Lubricant selection: ExxonMobil Polyrex EM grease is used by default for rolling bearings, and mixing different brands and types of grease is prohibited; Sliding bearings use rust proof oxidation inhibiting turbine oil, 2-pole motors use ISO VG32, and 6-pole and above motors use ISO VG68.

Guidelines for fat supplementation and replacement:

Rolling bearing grease cycle: 63XX series 1500-3000 hours, 222XX series 300-1000 hours; Under belt drive, high temperature environment (≥ 40 ℃) or dust environment, the grease replenishment cycle is halved.

Lubricating amount: Calculated based on the inner diameter of the bearing, 5-10g of grease should be added every 10mm inner diameter (such as 40g for 6310 bearing and 120g for 6318 bearing) to avoid excessive grease filling and bearing heating.

Greasing operation: Clean the oil drain hole on the bearing end cover before greasing, grease it during operation, run it without load for 10-30 minutes after greasing, drain the old grease, and then tighten the oil drain hole bolt.

Wear detection: Monitor the vibration value of the bearing through a vibration sensor. If the vibration value exceeds 3.8mm/s or the bearing temperature continues to rise (rolling bearings>95 ℃, sliding bearings>90 ℃), the machine should be stopped to check the wear condition of the bearing, and the bearing should be replaced if necessary.