HIGH SPEED ROTOR BALANCE TESTING

BRUSH AFTERMARKET PITTSBURGH

CONTENTS 03 LOW COST ROTOR BALANCING HAS ARRIVED 04 HIGH SPEED BALANCE PIT 05 WHY HIGH SPEED TEST A ROTOR?

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06 ADVANTAGES OF HIGH SPEED BALANCE TESTING 07 FACILITY TOUR

LOW COST ROTOR BALANCING HAS ARRIVED Since 1987 BRUSH Aftermarket, USA (formerly GMS) has offered a full range of inspection, testing, repair and retrofit services for all major generator brands. Now operating as part of the BRUSH group, customers can benefit from access to over 130 years of specialist generator manufacturer technical knowledge and expertise. With a commitment to enhancing operational capabilities at the Pittsburgh, PA facility, a multi-million dollar investment has seen the operationalization of the very latest diagnosis and repair technology, providing the fastest and lowest cost rotor balancing solution in the Americas. Together these changes signal the arrival of a new era of customer focused capability, supported and guaranteed with OEM expertise that’s delivered at the very lowest price. Low cost rotor balancing has finally arrived! Challenge us today for the lowest cost quotation: T: +1 412 829 7500 E: [email protected]

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HIGH SPEED BALANCE PIT Developed in conjunction with rotor balance technology leaders Schenck, the Pittsburgh facility is world class. A below ground bunker arrangement with DH9 pedestals and CABFLEX3 software shortens testing cycles that result in significant financial savings compared with dated technology alternatives. Technical capacities and capabilities: n Rotor weight range from 5,400 - 110,000lbs (55 US tons) n Max rotor diameter: 96 inches n Max rotor length: 510 inches n Max speed: 4,500rpm n Max rotor speed at 10% overspeed: 3,960rpm Investing in a state of the art high speed balance pit ensures that BRUSH Aftermarket can offer the most advanced OEM testing in the Americas today at the lowest possible price.

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WHY HIGH SPEED TEST A ROTOR? During outages rotors are often low speed balanced, especially after repairs or maintenance has been carried out. Without testing at high speeds future issues remain undetected resulting in excessive vibration, expensive repairs and costly downtime.

Any rotor that has undergone changes in its lifetime should have a high speed balance pit test. Changes in the structural stability of the rotor can be caused by a number of factors including previous repairs and modifications plus:

BRUSH Aftermarket recommends that rotors are high speed balanced whenever they operate above their first critical speed. Rotors are flexible (the longer they are the more susceptible to movement) and this can create an unbalanced effect leading to high vibrations and component failure. The correct placement of balancing weights is critical and during high speed balance pit testing all planes are accessible which ensures optimum placement.

n Insulation issues

There are a number of reasons why rotors require high speed balancing and there really is no alternative if you want to ensure the safe, smooth running of your generator.

n Rubbing

n Rewinding n Persistent vibration n Bowing n Spare rotors being incorrectly stored n Replacing the retaining rings

n Cracking n New blades being fitted or repaired.

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ADVANTAGES OF HIGH SPEED BALANCE TESTING High speed balancing testing at BRUSH accurately and quickly identifies current and potential faults through cutting edge technology and skilled engineers. Testing is comprehensive, providing enhanced rotor performance and lasting performance improvements: n Static and dynamic balancing operations through state of the art monitoring and software systems n Verification of the thermal stability of the winding and assembly with heat run testing regime n Verification of the structural integrity and establishment of final positions of components through 110% overspeed testing n Investigate for shorted turns and ground faults through flux probe, IR and winding resistance tests executed through the speed range n Dramatically improve rotor and overall machine reliability through reduction of imbalance induced vibration

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Once your rotor has been tested and the correct adjustments made it will run smoothly across the entire operating speed, however this is on the assumption that it is installed back inside the stator in the correct manner. Misalignment or issues with the stator itself can result in further issues; it is therefore strongly recommend that the entire process of removal, testing and refitting is undertaken by certified BRUSH Aftermarket engineers.

FACILITY TOUR

We welcome and encourage customers to tour our facility by prior arrangement, to meet our knowledgeable product experts and view first hand a rotor balancing in our dedicated inspection suite. Should a personal visit not be possible, remote monitoring is available via four in-pit cameras that deliver live HD streaming, providing complete oversight of the test procedure and progress against agreed schedules. We know that outage time can be costly and we try to accommodate our customers needs wherever possible. Our state of the art facility allows us to set up, balance and ship rotors out within a 24-hour window where required. Contact us today: T: +1 412 829 7500 E: [email protected]

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BRUSH AFTERMARKET 601 BRADDOCK AVENUE TURTLE CREEK PITTSBURGH PENNSYLVANIA 15145 UNITED STATES OF AMERICA T +1 412 829 7500 E [email protected]