Comprehensive maintenance and laser alignment of a high-power motor (9000 HP) – On-site service

• Equipment: Westinghouse synchronous motor, 9000 HP, 13.2 kV, 300 RPM.

1. Executive Summary

• Key Impact: Restored electrical and mechanical integrity of a critical 13.2 kV (extra-high-voltage) motor through a large-scale logistical deployment at the client's facilities.
• Technical Scope: The project combined disassembly, preventive maintenance of stator and rotor, varnishing, controlled drying and precision laser alignment.

2. Technical Challenge (The Problem)

• Asset Complexity: A 9000 HP Westinghouse motor operating at 13,200 volts. Because of its size and weight, moving it to a workshop was not viable, requiring a major intervention directly at its operating base.
• Operating Condition: The equipment required an in-depth validation of its insulation system and an alignment correction to prevent vibration that could compromise the coupling and the service life of the babbitt bearings.

3. Comprehensive Solution (Engineering by SIDELCA)

SIDELCA mobilized a complete mobile workshop, including 80- and 100-tonne cranes to handle the rotor.

• High-Voltage Electrical Maintenance:
• Diagnostic Testing: Initial megohm and polarization index measurements using equipment rated up to 15 kV.
• Winding Treatment: Cryogenic/dry cleaning and washing with a fast-drying dielectric product on the stator, rotor and exciter.
• Varnishing and Curing: Spray application of varnish and a controlled drying process with 25 kW portable equipment, plotting temperature versus time curves to guarantee optimal curing.
• Mechanical Engineering and Alignment:
• Bearing Maintenance: Verification of babbitt clearances using the Plastigauge method.
• Laser Alignment: Use of Fixturlaser STF 50 technology to correct axial and radial deviations, eliminating soft foot and thermal growth defects.
• Vibration Analysis: Certification of the final condition of the equipment through pre- and post-intervention vibration spectra.

4. Results and Value Metrics

• Dielectric Reliability: Substantial improvement in insulation levels, reaching a "Good" rating (index > 2) under IEEE standards.
• Mechanical Precision: The equipment was handed over with residual misalignment values within the "Excellent" range of the international CSI tables.
• Logistical Efficiency: Successful installation and removal of the heat exchangers and exciter components, ensuring immediate start-up after the intervention.

5. Project Technical Data