1,000+
rewinds executed
19 days
typical air-cooled generator stator rewind execution
100+
stainless steel stator rewinds on large liquid-cooled generators
Delivering reliably and effectively in more than 150 countries
Stator rewind services
Generator stator heritage and expertise
GE’s stator rewind services are standardized approach based on our deep, diverse generator heritage and knowledge. Stator Rewind services are a package of four modules: measurement*, engineering, bar manufacturing, and onsite rewind. Our proprietary processes and tools have been developed for quick, flexible execution across the value chain, with a focus on quality control at every stage.
*Applicable on other OEM generators
Stator rewind customer outcomes
- Proven and reliable technologies and processes, applicable to both OEM and other OEM generators
- Regional capabilities for faster mobilization supported by global expertise
- Onsite stator rewind integrated into a major turbine outage for minimal operational disruption
- Other OEM harmonization for rapid response
GE generator stator rewind features
- Stainless Steel stator bars for large liquid-cooled rewinds
- Stainless cooling tubes
- Tig weld connections between steel tubes and the water chamber
- Mechanical bolted connections between the stator bars and Teflon hoses
- Stator slot wedging technologies used and proven for decades across the 25 – 1,300 MW range of generators
- Digital applications help integrate processes from measurement onsite to field service execution
- References* across GE generator series
Stator rewind benefits
- Braze-free stator bar hydraulic circuit reduces the possibility of water leaks due to crevice corrosion
- Pre-assembled end winding basket reduces installation cycle time
- Provide you with the Option to re-use existing winding basket (contingent upon the material status, and applicable to legacy GE generators)
- Stainless steel technology that is less sensitive to cooling water chemistry (oxygen content, Ph) and variations in chemistry
A flexible offering for workshop and onsite applications
Rotor rewinds for GE and other OEM generator rotors
The strength of a flexible offering
Experience shows that typical operating incidents have the greatest impact on the field, which means the rotor is often the generator component requiring the most maintenance.
Whether the work you need is executed in a dedicated GE Generator Repair Shop or on site, GE provides a number of field rewind options to fit your needs.
With on-site rewinds you can benefit from reduced costs and fastest return to service.
For extended rewind scope such as upgrades you can rely on our repair shops equipped with high speed balancing pits.
Generator rewind
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Topack* T229-320 —105 MW—66 slots
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Topair * 50WY21Z-092LLT —210 MVA
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Large liquid-cooled generator operating in a coal power plant
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Rapid rotor rewind of a Topack T214-234
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Topack* T229-320 —105 MW—66 slots
-
Topair * 50WY21Z-092LLT —210 MVA
-
Large liquid-cooled generator operating in a coal power plant
-
Rapid rotor rewind of a Topack T214-234
Topack* T229-320 —105 MW—66 slots
Unit commissioned in 1993
- Feb 2015 forced outage due to stator earth fault led to an emergency repair (partial rewind)
- Slot discharges identified on two sister units
- The customer ordered stator rewinds on these two units in 2015
Scope
- Bar manufacturing
- Site execution
- Phase rings re-insulation
THE GE SOLUTION
28 days outage time “gear to gear” including additional scope
- 19 days rewind time including final standard tests and options
- Replacement of all bars with GE’s MICAREX insulation technology
- Lateral wedging by round packing
- Radial wedging with ripple springs
- Reuse of old end winding supports
- Phase rings re-insulation
Benefits
- Lifetime extension
- Update original configuration to increase availability
- Improved onsite processes to ensure shortest down time of both units
28-day
outage
19-day
rewind
Topair * 50WY21Z-092LLT —210 MVA
Unit commissioned in 1994 / GVPI
Customer suffered slot discharges
- Stator was suffering the problem of slot discharges
- 1998: DVV injection was performed
- 2001: stator suffered an earth fault, which was repaired with 3 top bar replacement
Scope
- GVPI bars extraction
- ewind with new bars
- Fast turnaround with high quality
GE SOLUTION
30-days rewind time including 10-day bar removal
- Replacement of all bars with GE’s MICAREX technology
- Lateral wedging with round packing
- Radial wedging with ripple springs
- Reuse of old end winding supports and phase rings
- Dedicated tooling and processes for GVPI stator rewinds
30-day
rewind
10-day
bar removal
Large liquid-cooled generator operating in a coal power plant
The rewind team were excellent in executing their duties, we lost time at the beginning of the project and they recovered significant amount of that time with no serious safety incident
High oil contamination created excess looseness, movement, and friction on the bars, which resulted in a gas into water leak on a bottom bar.
Project scope
- Supply rewind kit including stainless steel bars, cones, wedging system, phase ring, flux shields, temperature / vibration system, new water manifold
Customer benefits
- On-site rewind completed in 38 days
- Improved reliability and availability of the unit while extending its life
The use of the rewind kit available at the plant was an important factor for the quick recovery of the unit and illustrates the importance of having a full spare kit available.
38-day
rewind
Rapid rotor rewind of a Topack T214-234
Customer suffered electrical fault in service
- Third party performed internal inspection, removed retaining rings, repaired and re-installed rotor
- Shortly after re-commissioning the rotor developed an electrical fault again
- Customer decided to rewind the rotor
Scope
- Rewind with existing copper
- Renewal of interturn, slot wall and retaining ring insulation
- Fast turnaround with high quality required
THE GE SOLUTION
18-day, rapid rotor rewind
- Carried out at qualified local third-party workshop
- Renewal of all critical insulation components with latest technology
- 18-day duration inclusive of rotor low speed balancing
Benefits
- Plant fully operational 21 days after rewind start
- Electrical fault successfully corrected
- ISO requirements for vibration achieved
21-day
outage
19-day
rewind
Contact us
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