CBM of Electric Motors
As you know,
CBM = CAss + CM + RCA + CAPA but for rotating machines like motors, It can be, CBM = CAss + CM + Acoustic Lubrication + RCA + CAPA
CBM or Predictive Maintenance (PdM) of Electric Motors, includes CM of Motors, RCA & CAPA. Electrical Motors are of two types, AC & DC. The AC motors are of two types, LV & MV HV. The CM procedure for each type of these motors is not common, rather Visual Inspection & Electrical Testings differs.
Condition Monitoring (CM) of Electrical Motor includes Thermography, Ultrasound Measurements, Vibration Measurements, Vibration Probing Study, Visual Inspection, Electrical Measurements. Few of the electrical Measurements are offline.
The online electrical measurement includes monitoring & recording current & Voltage, periodically. Whereas the offline electrical measurements include MCSA, Surge Comparison Testing, Winding Resistance Testing, Insulation Resistance Testing, Polarization Index Testings. For MV & HV motors, these tests added with Tan δ & Capacitance Testing & High Voltage Testing (for the new motor). The frequency of offline monitoring maybe once or twice in a year.
The visual testing in DC Motors includes inspection of sparking at the commutator, length of carbon brushes, etc.
We have a state of the art facilities at our other company Omkar Engineers, Inc and we can refurbish electric motors up to 20 Megawatt & up to 11 kV voltage ratings. We do onsite overhauling/ bearing replacement jobs for large motors. Please read, Refurbishing of electric Motors.
At our works, we manufacture & replace winding coils up to 11 kV voltage rating. We rectify core faults by refurbishing/staggering core. We re-insulate each of the core stampings before assembling it. Any other part, like bearing housing, is manufactured & replaced with accuracy if repair is not possible.
The Acoustic Lubrication needs to be added in the contract, in order to maintain the condition of the bearings.
The process of CBM of Electric Induction Motor/DC Motor or Predictive Maintenance of Induction Motor/ DC Motor includes condition assessment of the motor to know the anomalies with the motor, then Corrective actions taken to restore the health of the motor, followed by CM visits to record the parameters under monitoring & acoustic greasing is done during same visit, the trend of each parameter is maintained & in case of any symptoms – RCSA is done & then CAPA is carried out to restore the condition.
