Rotor Services

Complete servicing for any make of rotor

Our 50,000 square foot manufacturing plant in Turtle Creek, Pennsylvania is equipped with two heavy duty lathes and a complete compliment of milling machines, so we can confidently and competently handle any operation on any rotor of up to 100 tons.

Services include:

  • Inspection
  • Testing
  • Rewind
  • Machining
  • Life extension
  • Engineering

A ready supply of retaining rings

To make sure your generator is back up and running efficiently as quickly as possible, we make sure we’re always well stocked with 18Mn-18Cr retaining rings to fit 1,000 different rotors.

Tooth-top cracking eliminated permanently

Tooth-top cracking under the retaining ring is a common problem. But Brush Aftermarket has devised a patented procedure that doesn’t just defer the issue, but permanently resolves it for the life of the rotor. We also offer NDE examination and complete wedge land repair solutions for the length of the rotor body.

Exciter Services

From straight forward repairs to performance enhancements. 

Our expert teams are highly experienced in the design, manufacture, maintenance and testing of brushless exciters and they can re-engineer components to improve performance.  If you’re due an upgrade, we can now supply new brushless exciters to our clients too.Our services include:

  • Repairs
  • Rebuilding components
  • Refurbishment program to disassemble all removable components, testing each electrical component to identify its status
  • Component replacement
  • Rebanding services
  • Complete rewinds of the stator and rotor winding assemblies
  • PMG rewinds
  • Full speed balance of all exciter rotors in a state-of-the-art balance facility
  • Emergency excitation services, including a mobile exciter, which can be brought to site, and swap-out brushless exciters for use during refurbishments
  • Electrical testing, including:
  •       RTD Resistance Test
  •       RTD Insulation Resistance
  •       Thermocouple Continuity
  • Supply of new brushless exciters
  • Exciter Housing Modifications

Housing modifications reduce risks and improve operation

  • Brush Aftermarket can carry out a Positive Pressure Vent Modification (PPVM) to your existing exciter housing which has been proven to significantly reduce the rate of dirt contamination and mitigate the potential hazard of hydrogen ingress.
  • Housings are modified so the inside pressure is at a higher level than the outside, which reduces the intake of dirt and contamination during operation.

Stator Services

For every aspect of generator maintenance, our service is as thorough and well thought through as our approach.  And we like to think our standard services are anything but standard, as they’re carried out with such precision and expertise.  Services include:

  • Inspections, electrical and mechanical testing
  • Complete rewind
  • EL-CID, loop test and end winding stiffness (“Bump”) testing and analysis
  • Patented end winding vibration services
  • Vibration monitoring
  • Full or partial rewedge

End winding vibration resolution services

To expand our services, we’ve developed a series of patented retrofit solutions to end winding vibration that do not require a rewind of the stator.  These options have been developed on a building block approach and we’ve been using them successfully since 1993. 

Vibration monitoring systems

Stator winding vibration monitoring systems provide information on both electrically and mechanically inducted vibrations being experienced on the end windings.  Depending on your set up, the systems can be configured to provide information at the generator itself or via continuous monitoring in the control room.  


Brush Aftermarket U.S. has various balancing equipment whereby rotors can be tested against nominal speed.  

Rotor Mass Limitations

  • Maximum weight with Symmetrical loading - 110,000 lbs
  • Minimum recommended weight - 5,400 lbs
  • Maximum weight per support - 55,000 lbs
  • Maximum permissible intermittent centrifugal force per support - 113 tons

Rotor Dimensions

  • Maximum diameter over bed with risers (subbases) DH7 only - 96 in
  • Maximum rotor length (including stub shaft)/bedplate length - 510 in
  • Maximum distance from coupling flange to farthest bearing - 455 in
  • Minimum distance between support bearing centerlines - 35.43 in
  • Maximum recommended journal diameters - 18.7 in
  • Bore diameter of sleeve bearing housing - 25.6 in
  • Maximum oil capacity per bearing - 106 gpm
  • Maximum rotor speed for balancing, testing or overspeeding - 4500 rpm
  • Maximum ambient temperature in test chamber - 175 °F

Spare Parts

In order to increase the operating life of machines and equipment, Brush Aftermarket offers a replacement parts service.  We offer a wide variety of high quality parts for our own machines and from other manufacturers including:

  • Individual components such as diodes and fuses
  • Integral parts such as keys, spools and bearings
  • Essential parts are in stock such as replacement rotors, stators, and generators which are mechanically and electrically interchangeable

Since it is important that your machine continues to operate properly, we advise keeping a supply of basic parts for your machine on hand.  This can, in combination with a good maintenance program, considerably reduce the duration of production failure should a breakdown occur.  All commonly used parts from Brush manufacturers are in stock in our extensive parts facility in the US.  Parts can then be quickly delivered to the necessary location. 

24HR Service

SERVICE 24 is the 24/7 Technical Support Helpdesk from Brush Aftermarket.  It provides Customers, Representatives and Field Service Engineers with a Technical Support Service 24/7/365, operated by highly experienced Brush Service Engineers with wide-ranging experience covering both mechanical and electrical disciplines.  SERVICE 24 is operated from our home office.  You can reach us at:  +1-888-723-2975 or via email at  SERVICE 24 has been created to respond without delay to operational technical assistance and emergency machine breakdown support.  Any other issues requiring normal Aftermarket business support including spares inquiries, sales and scheduled field support activities should be addressed as before to your regular Brush Aftermarket contact points.