TCO: IPS PowerSeal™ Rewind Provides Up-rate and Efficiency GainMegan Thompson
Motor Type: AC Induction
A newsprint paper mill had thirty-six refiner motors that were commonly pushed beyond their 5000 HP rating, resulting in multiple failures and unplanned downtime. The motor OEM had recommended rewinding the motors to uprate to 5620 HP, but several of these rewinds failed prematurely.
IPS rewound all thirty-six motors with our PowerSeal® medium-voltage VPI engineered insulation system to deliver:
• Motors uprated to 5,620 HP
• 3% increase in motor efficiency, to 93% from 90%
These PowerSeal rewinds included our standard 5-year warranty with these reliability upgrades:
• Designed circuit rings for easer lead replacement and cooler operation
• Elimination of rigid mounting of support rings, for thermal expansion of coils independent of frame
• Surge rope and steel surge rings with felt blocking for rigid setup and ample cooling
• TIG welding of lamination finger supports to keep them in place during operation
• IPS rewinds delivered almost $500,000 in annual savings (>$3,400,000 in total savings over seven years):
• IPS rewinds were approximately $35,000 less than competitive rewinds.
• Zero failures equal zero unplanned downtime, conservatively estimated at $10,000 an hour.
• 3% efficiency gain resulted in an estimated $43,468 in annual power cost savings per motor.
Download the complete case study and calculations below: