Dc Motor Repair

By Author: Jared Olson
Total Articles: 2
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When we consider dc motor rewind, it normally includes restorationand upgrading of the motors, including its insulation system. The motors range from 1¼ to 6000 hp, and go through a wide range of tests to discover their flaws and before going to arrive at a predictive maintenance formula for their rebuilding, before pressing them back into service.|For evaluation of ac motor repair various tests are made which include Motor Circuit Evaluation (MCE), vibration analysis, surge, growler, hipot, core loss, bearing insulation and polarization index profile (PIP). For motors with high HP, rewinding, repair and re-manufacturing are also undertaken.Likewise, rewinding, repair and re-manufacturing are done for high HP motors The maintenance plan for the older units need to be taken into account for improving their dependability, using preventive and prognostic maintenance augmentation, inventory improvements, rotating spares, better tools, shop planning, specific ...
... training, and proper execution of a new computerized maintenance program. Rewinding, repairing, and re-manufacturing of large generators are also done by good and wide-ranging workshops. Knowledge of the maintenance department is important in knowing the various causes of failure and use new and updated technologies for collecting information to begin the condition evaluation process.Refurbishment The cycle of restoration followed for almost all of the project motors followed this order:Removing Transport of motor to assigned restoration facilityDocumenting of nameplate and other descriptive information visible without disassembly To guarantee safe value for energizing motor in the shop resistance-to-ground is tested.Running motor on test stand for warming up and vibration analysis| Vibration analysis after operating motor on test stand to warm up.}Performing the off-line, low voltage Motor Circuit Evaluation (MCE) tests. Disasemble, visual inspection and recording of conditions and other characteristics observed (such as typeof bearings used and number of rotor bars). Carrying out after cleaning search for mechanical flaws post cleaning and drying of componentsCarrying of core loss, hipot, growler, surge, and bearing insulation tests depending on the size andkind of motor to be rebuild Depending on the size and type of motor to be renovated, carrying of core loss, hipot, growler, surge and bearing insulation tests Appointing leader and shop supervisor for any out-of-scope modifications and repairs to be done. Performing authorized electrical and mechanical repairs, modifications and rebuilding(including cure winding insulation and dip or over-spray).Dynamically balancing of rotating elements and reassemble motors.Attachment of new or other nameplate with the latest motor characteristicPerforming post rebuilding shop tests (motor circuit analysis and vibration analysis)Transporting to plant and reinstallingPost installation, various tests are performed, like baseline tests, MCE test after making electrical connections and before connecting it, and vibration examination and on-line electrical study in the shortest possible time subsequent to start up. Attending to most frequentpost installation issues such as making follow-up adjustments as needed, correcting any after installation circuit resistance, imbalance and adjustment of mechanical alignments.Corrosion removal- Requires sand blasting and rods for cleaning the interior of cooling channel.Pre-assembly balancing- All rotating elements should be dynamically balanced preceding reassembly of the motors. Reassembly - Replacement of sleeve bearings and shaft sleeves showing any tainted condition and all roller bearings.Shop testing- Motors should be run closest to normal operating voltage and checked for vibrations. Rotor influence check (RIC) - It is conducted as a quality examination for the reassembly and used as a baseline for future.Testing after installation - After connecting each motor to its electrical circuit, but before energizing it for the first time, it's subjected to another MCE test to ensure balance of inductance and resistance of the complete circuit and having desired values of resistance-to-ground and capacitance-to-ground.Magnetech Industrial Services offers total generator and Electric Motor Repair, reconditioning, and remanufacturing. We service all makes and models of AC and DC motors and generators and also offer diagnostics and field services including complete preventative maintenance and 24/7 emergency service. Our in-house engineering team provides performance verification and analysis, motor redesign, and UL re-rating. We excel at solving your equipment problems - on time, to specification, and within budget.