Download Wood Group Turbine Generator Services Overview

Generator Services
WGGS Capabilities
Presentation
Generator Services
Our Location
LOCATION: New
Wood
Group USA
Farmington,
Four Mexico,
Corners,
Generator
New Mexico
Services, Inc.
Generator Services
Our Focus
Turbo Power
Hydro Power
Petroleum
Steel
Paper
Turbo Generator Stators and Rotors
Generator Services
Our Focus
Turbo Power
Hydro Power
Petroleum
Steel
Paper
Hydro Generator Stators and Rotors
Generator Services
Our Focus
Turbo Power
Hydro Power
Petroleum
Steel
Paper
AC Electric Motor Stators and Rotors
Generator Services
Fully Integrated Capabilities
/ Project Management
Coil Manufacturing
Field Services
Roebel Bars
Multi Turn Coils
Inspection & Diagnostics
On Site Stator Rewinds
Preventative Maintenance
Fully integrated
coil facility
design,
manufacture,
testing
VPI coils,
B-Stage
Up to 15 KV
Short Lead
Times
Generator/Motor Shop Services
Stator/ Rotor Rewinds & Core Restacks
In stock Retaining Rings, Full Machining
capabilities
High Speed Balance and Testing
Rotor Clean
Rooms
for Rotor
rewinds & repairs
High Speed
Bunker
Electrical Testing
at speed
Rotor coil
manufacture
Cylindrical and
salient pole
windings
Site Inspection
and tests
Generator
Monitoring and
On-line
Diagnostics
On-Site Repairs
(rewedge, end
winding stability
system, core
restack/rewind)
Generator Services
Technical Presentation
Presentation Chapters
WGGS Generator Assessment Program Tour
WGGS Electric Motor Rewind Tour
WGGS Hydroelectric Generator Tour
WGGS Project Management Philosophy
WGGS Generator and Electric Motor Wear Factor Tour
WGGS Turbine Generator Rotor Tour
WGGS Turbine Generator Stator Tour
Generator Services
WGGS
Generator
Assessment
Program
Tour
Generator Services
Technical Presentation
Generator Assessment Program Tour
Wood Group Generator
Services, Inc.
Generator Assessment Program (GAP)
Generator Services
Technical Presentation
Generator Assessment Program Tour
Generator Assessment Program, Option #1
12 hour Assessment (to fit “engine borescope”)
Unit condition - Generator assembled but inspection access covers
removed
Inspections/tests performed:
● Borescope inspection of armature winding, rotor winding and blocking (as
accessible), stator core step laminations and fingerplates
● Perform tests on rtd’s, armature winding, and rotor winding
● Armature Winding Test – IR, PI and Res.
● TGR Test – IR, PI, Res., and Impedance
● Exciter inspection - Visual inspection, insulation resistance tests
Generator Services
Technical Presentation
Generator Assessment Program Tour
Generator Assessment Program, Option #2
3-4 Day Assessment (to fit “valve inspection” or “auxiliary inspection”)
Unit condition - Rotor installed but top half of end brackets removed
Inspections/tests performed:
● Visual and Borescope inspection of rotor winding and blocking, stator core
laminations and fingerplates (as accessible).
● Insulation tests on rtd’s, armature winding, and rotor winding.
● Winding tests – IR, PI, and Resistance - (armature winding and rotor winding).
● Core tightness checks (visual indications of looseness).
● Doble - Power Factor and Tip up.
● Corona tests, as assessable, to determine areas and severity of any corona
activity.
● Step voltage tests (d.c. step voltage / dielectric absorption or high potential) to
determine insulation integrity of armature windings.
● End winding stability test (end winding basket frequency check).
Exciter inspection:
● Visual inspection.
● Insulation resistance tests.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Generator Assessment Program, Option #3
7 – 10 Day Assessment (to fit “cylinder inspection” or “major inspection”)
Unit condition - Rotor removed
Inspections/tests performed:
● Visual inspection stator and rotor
● Borescope inspection of rotor winding and blocking (as accessible)
● Perform tests on rtd’s, armature winding, and rotor winding.
● Winding resistance checks (armature winding and rotor winding).
● Core tightness checks
● Corona tests to determine areas and severity of any corona activity
● Step voltage tests (d.c. step voltage / dielectric absorption or high potential) to
determine insulation integrity of armature windings
● End winding stability test (end winding basket frequency check)
● Core El Cid test
● Wedge Tightness Detection
● Doble Power Factor and Tip up
● Rotor impedance and pole balance tests
● Generator rotor retaining ring NDE inspection (based on OEM requirements)
Exciter inspection:
● Visual inspection
● Insulation resistance tests
Generator Services
Technical Presentation
Generator Assessment Program Tour
Generator Assessment Program, Option #4
3-4 Day Assessment (to fit “valve inspection” or “auxiliary inspection”)
Unit condition - Rotor installed but top half of end brackets removed
Inspections/tests performed:
● Visual and Borescope inspection of rotor winding and blocking, stator core
laminations and fingerplates (as accessible).
● Insulation tests on rtd’s, armature winding, and rotor winding.
● Winding tests – IR, PI, and Resistance - (armature winding and rotor winding).
● Core tightness checks (visual indications of looseness).
● Doble - Power Factor and Tip up.
● Corona tests, as assessable, to determine areas and severity of any corona
activity.
● Step voltage tests (d.c. step voltage / dielectric absorption or high potential) to
determine insulation integrity of armature windings.
● End winding stability test (end winding basket frequency check).
● Robotic El CID core test (as accessible).
● Robotic wedge tightness mapping (as accessible).
Exciter inspection:
● Visual inspection.
● Insulation resistance tests.
Generator Services
Generator Assessment Program Tour
Generator Assessment Program, Option #5
7-10 Day Assessment (to fit “cylinder inspection” or “major inspection”)
Unit condition - Rotor installed but one top half of end bracket
removed
Inspections/tests performed:
● Visual and Borescope inspection of rotor winding and blocking, stator core
laminations and fingerplates (as accessible).
● Insulation tests on rtd’s, armature winding, and rotor winding.
● Winding tests – IR, PI, and Resistance - (armature winding and rotor winding).
● Core tightness checks (visual indications of looseness).
● Doble - Power Factor and Tip up.
● Corona tests, as assessable, to determine areas and severity of any corona
activity.
● Step voltage tests (d.c. step voltage / dielectric absorption or high potential) to
determine insulation integrity of armature windings.
● End winding stability test (end winding basket frequency check).
● Robotic El CID core test (as accessible).
● Robotic wedge tightness mapping (as accessible).
Exciter inspection:
● Visual inspection.
● Insulation resistance tests.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Off-Line Inspection, Tests & Examinations
Insulation Resistance Test
An insulation resistance test is a low voltage test (typically 500 to
2,500 VDC) utilized to determine only the most general condition
of a winding. It can indicate only the most severe or significant
degree of insulation damage and is typically used as a prelude to
most searching tests.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
Polarization Index Test
A polarization index test is another relatively low voltage
examination. Once again, this test is utilized to determine only the
most general condition of a winding. A P.I. test is generally
performed in order to determine whether or not more stringent
testing can be performed.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
DC Ramp or Step Voltage Test
The data concerning winding condition offered by a DC high potential
test can be significantly improved by observing the difference in current
as the test voltage is increased. If a flaw exists in the ground wall
insulation system, a failure is often preceded by an abrupt rise in
current. This allows the operator to terminate the test at the first sign
of warning.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
Power Factor Tip-Up Test (Doble)
Power Factor Tip-up testing examines the windings at various
voltage levels. This test is significant in the degree of detail it
can provide with regard to the serviceability of a winding.
Factors such as contamination, corona suppression system
degradation, partial discharge activity, insulation delamination,
and voids all impact the results of this testing.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
Corona Camera Examination
A corona camera is a specially designed video instrument, utilized to record
the presence of partial discharge activity other wise invisible to the naked
eye under normal turbine deck lighting conditions. With this instrument one
can see what a particular winding look like under normal operating
conditions.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
Wedge Tightness Mapping
Computerized wedge tightness testing is a method of precisely
measuring the stator slot wedge system for its degree of tightness
within the core iron wedge grooves. An automatic hammer, attached
to an accelerometer, is used to tap each and every individual wedge.
The computer measures, and compares all reading against
predefined calibration parameters.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
End Winding Stability Examination
Premature winding failure may occur due to excessive end winding
vibration. Large turbine generators and hydro generators are most
susceptible. Routine measurement of vibration amplitude and frequency
is important in detecting looseness, which can lead to fatigue and failure
of copper conductors and insulation systems.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
Winding Resistance Measurements
Performed with a Digital Low Resistance Ohm (DLRO) meter,
this test measures the resistance across individual phases,
phase groups, or coils. Measurement of winding resistance can
determine incorrect connections, cold or broken braze joints,
severe mismatches, and/or opens.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
Electro-Magnetic Core Imperfection Detection (El CID) Test
Electromagnetic Core Imperfection Detection (EL CID) core testing is a
means by which the integrity of stator core intra-laminar insulation can
be measured, utilizing minimal electrical input to excite the iron. EL
CID is excellent in its ability to pin point and accurately measure even
the smallest defect.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
AC Impedance Test
An AC impedance test is performed by inducing into the rotor windings
incrementally increasing voltages. The voltage and amperage are
measured and recorded. The ohm values are calculated and graphed
against the applicable voltage levels. This is another method of
testing for turn-to-turn shorts. An AC impedance test may be
performed either with the rotor at rest, or at any desired speed.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
AC or DC Pole Drop Test
A pole drop test is performed by inducing a voltage into a rotor
winding, measuring the voltage drop across each individual pole,
and then comparing the two against one another. If the reading
are off more than 5-percent, turn-to-turn shorts are suspected in
the pole generating the lower reading.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
Static Turn Insulation Integrity Test (STIIT)
A static turn insulation integrity test (STIIT™) is utilized to measure and
compare readings for each and every individual coil within a 2-pole rotor.
Readings for like coils of opposing poles are compared to one another as well
as industrial standards. Difference in readings are applicable to the degree of
turn-to-turn shorts within any particular coils.
Generator Services
Technical Presentation
Generator Assessment Program Tour
Tests, Inspections, and Examinations
Off-Line Inspection, Tests & Examinations
Visual Inspection
If any of the afore-mentioned tests produce negative results, a thorough visual
inspection is imperative. In other instances, a visual inspect will produce results,
which indicate further testing. A visual inspection is quite inexpensive, while
being extremely telling about the condition of your generator. WGGS archives all
photographic record of each and every visual inspection performed.
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Generator Services
WGGS
Electric
Motor
Rewind
Tour
Generator Services
Electric Motor Rewind Tour
Â
Wood Group Generator Service, Inc. (WGGS) reconditions, repairs, rebuilds,
and rewinds electric motors of all shapes and sizes. This particular unit failed
to ground when a balance weight came loose and struck the stator core iron.
Typical
Project
Status
Report
Generator Services
Electric Motor Rewind Tour
The existing stator windings
are carefully removed.
The iron damage was severe
and deep.
A view of the failed stator coil,
melted in half by the event.
The customer elected to
replace the entire stator core.
The existing stator core iron
was removed and disposed of.
The existing stator housing
was grit-blasted clean.
Generator Services
Electric Motor Rewind Tour
All new compression thrubolts were manufactured.
All new end compression
rings were manufactured.
All new stator laminations
were procured.
The new compression thrubolts were installed.
The new core iron was
installed and compressed.
The new core iron was full flux
core tested and El CID tested.
Generator Services
Electric Motor Rewind Tour
Â
Wood Group Generator Service, Inc. (WGGS) offers our OMEGA-Pac and
OMEGA-Vac insulation systems for generator and electric motor stator
windings.
TM
TM
Generator Services
Electric Motor Rewind Tour
The throw of new stator
windings is installed.
The installation of the new
windings approaches the lap.
The lap windings are lifted as
the last coils are installed.
A new stator wedge system
ins installed.
The stator end connections
are formed, brazed, and taped.
A view of the completed
windings.
Generator Services
Electric Motor Rewind Tour
The motor rotor was at-speed
balanced at 1,800 RPM.
The rewound motor was
assembled and prepared for
delivery.
The completed product being
loaded out for delivery.
Typical
Project
Final
Report
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Generator Services
WGGS
Turbine
Generator
Rotor
Tour
Generator Services
Turbine Generator Rotor Rewind Tour
Â
Wood Group Generator Service, Inc. (WGGS) utilizes a very select group of
Heavy Haulers, highly experienced with the handling of Turbine Generator
Rotors (TGRs). Seismic recording of the transport is available upon request.
Typical
Seismic
Recording
Report
Generator Services
Turbine Generator Rotor Rewind Tour
Â
A complete and comprehensive incoming mechanical, electrical, and visual
inspection is performed on every TGR as received and prior to disassembly.
Typical
Incoming
Inspection
Report
Generator Services
Turbine Generator Rotor Rewind Tour
Â
All TGR retaining rings are removed by highly experienced WGGS Generator
Techs, utilizing induction heating equipment. No open flame will ever touch
your rings.
Typical
Project
Status
Report
Generator Services
Turbine Generator Rotor Rewind Tour
Block migration and partial
end winding collapse.
Pole face block breaking and
migration.
Tooth top cracking.
Aluminum saddles fitted over
soft copper.
Severe end winding
contamination.
Significant end winding turn
elongation and deformation.
Generator Services
Turbine Generator Rotor Rewind Tour
Â
Existing windings are carefully removed, cleaned, straightened, annealed as
required, further cleaned, and inspected in preparation for re-installation.
All existing winding
copper is subjected
to a metallurgical
analysis prior to
reuse.
Generator Services
Turbine Generator Rotor Rewind Tour
Picture-Frame Style Coils:
All new CC107 Silverbearing copper is
used.
CNC mills accurately
profile the corner
connections.
Continuous-Wound Style Coils:
Again, all new CC107
Silver-bearing copper
is used.
Spools of new copper
are setup on a tension
dereeling devise
Corner connections
are silver-brazed by
qualified WGGS
Techs.
Each and every new
coil is carefully
scrutinized prior to
installation
Continuous-wound
coils are generated on
the “Merry-go-Round”.
All end windings are
annealed in order to
facilitate forming.
Generator Services
Turbine Generator Rotor Rewind Tour
Â
All TGR components are thoroughly cleaned, inspected, and rehabilitated as
part of the rewind process.
The rotor body forging
is grit-blasted, utilizing
a soft media.
Following cleaning,
the rotor body forging
is thoroughly NDE’d
All rotor body wedges
are cleaned and NDE’d
for cracks.
All wedges are hand-fit
to their respective slot
locations
The existing retaining
rings are cleaned and
NDE’d.
The radial and bore
copper assemblies are
reconditioned.
The fan assemblies,
coupling, etc, are
cleaned and NDE’d.
The existing end
winding blocking is
inspected for re-use.
Generator Services
Turbine Generator Rotor Rewind Tour
Â
WGGS has the in-house capability to manufacture each and every component
found on a Turbine Generator Rotor.
Special retaining rings
insulation.
Al new oil defectors,
seals, and baffles.
18Mn18Cr retaining
rings from our stock
inventory.
All new diffuser
blades.
All new fan blades and
blower hubs.
All new rotor body
wedges, including
specialized plating.
All new end winding
blocking.
Completely new diode
wheel assemblies.
Generator Services
Turbine Generator Rotor Rewind Tour
Â
The WGGS rewind methodology produces a highly accurate and concentric
winding, assuring a smooth-running TGR.
All new ground wall
insulation is utilized
on every rewind.
The compressed
windings are induction
baked.
All TGR’s are rewound
in an environmentallycontrolled clean room.
The winding heads
and temporary
blocking is removed.
Temporary blocking is
inserted into the end
winding.
The permanent
blocking system is
installed.
Specially-manufactured
compression fixtures are
installed.
The windings are
compressed and
induction baked again.
Generator Services
Turbine Generator Rotor Rewind Tour
Â
As part of the final assembly process, all new retaining ring insulation is
installed. Induction heating equipment is utilized to install the retaining rings.
Typical TGR
In-process
Report
Generator Services
Turbine Generator Rotor Rewind Tour
Â
The fully assembled TGR is loaded into the WGGS bunker and subjected to
high speed balance, over speed confirmation, and running electrical testing.
Typical High
Speed Balance
Report,
Including Flux
Probe.
Generator Services
Turbine Generator Rotor Rewind Tour
Â
The final acceptance process consists of a myriad of highly detailed
operations in order to assure that you receive a quality end product.
Our large lathe is
utilized to grind and
polish journals.
All final acceptance
electrical testing is
performed.
The entire TGR is
hand-cleaned and
visually inspected.
The TGR is rotated while
final run outs measured
and recorded.
A borescopic inspection
is performed under the
retaining rings.
The finished product
is loaded out and
vacuum-sealed.
Components such as
fan blades are
mounted and secured.
Protected and
secured, the TGR is
ready for delivery.
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Generator Services
WGGS
Turbine
Generator
Stator
Tour
Generator Services
Turbine Generator Stator Rewind Tour
Â
A WGGS Generator Assessment Program (GAP) may indicate a terminal
condition, such as extreme Partial Discharge Activity (PDA).
Typical
Project
Status
Report
Generator Services
Turbine Generator Stator Rewind Tour
Â
WGGS Generator Specialists carefully remove the existing coils or bars and
prepare the stator core iron to accept all new and modern windings.
Typical
Engineering
Design &
Drawings
Generator Services
Turbine Generator Stator Rewind Tour
Â
All new WGGS OMEGA-Pac Roebel half-coils can be designed and
manufactured. As an alternative, an all new WGGS OMEGA-Pac insulation
system can be installed over top of the existing copper. Application of IEEE
1043 endurance testing is a standard operating procedure.
TM
TM
Generator Services
Turbine Generator Stator Rewind Tour
Â
WGGS Generator Technician install the OMEGA-Pac new windings,
following highly detailed written procedures and processes.
TM
Bottom bars are laid-in
over new or rebuilt
surge ring assemblies.
Bars are carefully
spaced and lashed to
the surge rings.
An all new stator slot
wedge system is
installed.
In process high potential
testing is performed
prior to connection.
Six rows of blocks and
ties, where the OEM
winding had only three.
Top bars installed and
tightly side-packed
into position.
No less than three (3)
El CID tests are
performed.
The second El CID test
is performed after
wedge installation.
Generator Services
Turbine Generator Stator Rewind Tour
Â
With the new winding installed, the WGGS Generator Technicians focus on
processing the end connections and final processes.
End winding
connections are
induction brazed.
Bar-to-circuit ring
connections are
brazed and insulated.
The end connection
boots are carefully
installed.
The completed windings
are enclosed and ovencured.
Additional filler
blocking is installed
behind the clips.
The completed and
fully-cured windings
are allowed to cool.
Epoxy/Glass boots are
filled with a special
epoxy.
The completed
windings are coated
with epoxy-buff paint.
Generator Services
Turbine Generator Stator Rewind Tour
Â
The final acceptance process consists of a myriad of highly detailed tests in
order to assure that you a quality end product. Assemble then ensues.
Typical
Project
Final
Report
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