Erosion/Corrosion Resistant Coatings for Compressor Life Extension

Erosion/Corrosion Resistant
Coatings for Compressor
Life Extension
Ted Traynor/Bob Tollett
Liburdi Turbine Services
Email addresses:
[email protected]
[email protected]
Phone: 1-905-689-0734
Facilities
Main Offices
Liburdi Automation Inc.
Liburdi Engineering Limited
Liburdi Dimetrics Corporation (USA)
Military Turboprop
Erosion and Performance
Development of RIC for
T56 Compressor Blades
T56 turboprop engine evaluated
by NRCC
Coated all 14 stages of blades
No measurable fatigue penalty
to new airfoils
T56 turboprop application
qualified by Rolls-Royce
In production for OEM RollsRoyce, over 4000 Engines
delivered
In production for commercial
overhaul market
Courtesy of
Courtesy of
Courtesy of
Erosion/Corrosion
of Compressors
• Fly on condition or 10% loss in HP on Military Fleets
• Largely dependant on field of operations
• Can be severe on Turboprop lower altitude Island
Hoppers with a combination of erosion / corrosion
causing HCF failures.
Performance Retention
Under Erosive Conditions
RIC Coating on GE T-64 Turboprop Compressor Airfoils
100
Uncoated Airfoils
80
RIC Coated Airfoils
100
80
60
Uncoated
and coated airfoil profiles
compared to new profile (- - - - -)
40
60
40
20
20
0
0
Remaining
chord150
section
at tip250
50
100
200
Average service life [%]
0
0
Remaining
chord 200
section250
at tip
150
100
50
Average service life [%]
Electron Beam
Reactor Design
•
•
•
•
North American designed & built EB
Process and coaters.
Largest EB-PVD Chambers available
capable of coating multiple blades and
or vanes at a time.
Pure evaporation of multiple sources
free of spits or macro particles.
Greater scalability for high capacity
production.
Windows based PC controller
technology.
EB Process versus
Arc PVD
• Inherent < 5µ surface
finish
• No need to blast
parts for adhesion
• No reduced Fatigue
debit from blasting
Layering Process
Versatility
•Multiple fed sources allow for a variety of
coating chemistries within a single coating
cycle.
•Uniform Nano layered structures of Ti, Cr,
Al,Si in ceramic and alloyed deposits by ebeam evaporation can provide superior
performance in Erosive / Corrosive
environments.
 Coatings may be tailored on a stage by
stage basis to address stage specific wear
mechanisms such as high angle vs. low
angle erosion.
Erosion at 30 Degree
Angle of Attack
Erosion at 30° attack angle
18
16
Uncoated 17-4PH
14
EPS-10705, Gen I
Multilayer, Gen II
Mass loss, mg
12
Gen III
10
8
6
4
2
0
0
500
1000
1500
Mass of 240 grit, g
2000
2500
3000
Erosion at 90 Degree
Angle of Attack
Erosion at 90° attack angle
9
8
Uncoated 17-4PH
EPS-10705, Gen I
7
Multilayer, Gen II
Mass loss, mg
6
Gen III
5
4
3
2
1
0
0
50
100
150
Mass of 240 grit, g
200
250
Erosion Resistance
Tests conducted at ambient conditions with 100µ Al2O3 at 70m/s
RIC
GEN I
650 g to
breakthrough
RIC
GEN II
1300 g to
breakthrough
RIC GEN
III
7Kg to
breakthrough
Corrosion Resistance
Hours passed in Salt Fog test
450
Hours of Salt Fog test
400
350
RIC GEN
III
300
250
200
150
100
RIC
GEN I
RIC
GEN II
50
0
I
II
Coating generation
III
Corrosion Resistance
RIC
GEN I
40 hrs to pitting
RIC
GEN II
60 hrs to pitting
RIC GEN
III
400 hrs some
stains no pitting
Fatigue Properties
Properties: Airfoils
• National Research Council of Canada fatigue
testing of RIC coated T56 blades found:
“… there is no significant change in fatigue life”
relative to uncoated blades.
Both 17-4 PH & Ti-6Al-4V blades were tested.
Fatigue
Fatigue Properties Properties:
Airfoils
• Results confirmed by Naval Aviation
Depot study (T58-GE-16 Compressor
Blade Liburdi Titanium Nitride Coating
Fatigue Test):
“The Titanium Nitride coating does not
reduce or significantly increase the
fatigue life of the T58 compressor blades.
The Titanium Nitride coating does not
significantly change the natural frequency
of the T58 compressor blades”
Effect of Roughness
on SFC
Typically a LIBURDI RIC Super Polish Finish of 8µInches will
save 1-1.5% SFC
0.8%
Typical Effect of Compressor Stage Surface Finish
on the Engine Performance
0.6%
S.F.C. Change (%)
Other ARC ER Coatings
0.4%
0.2%
0.0%
0
10
20
30
40
50
Surface Roughness (µIn)
-0.2%
-0.4%
-0.6%
Hydraulic Sm oothnes s
-0.8%
Liburdi EBPVD RIC
-1.0%
60
70
COURTESY OF
COURTESY OF OKLAHOMA
CITY
AIR LOGISTICS CENTER
TEAM TINKER
T56-A-7B/-15
Technical Issues
May 2007
Tim Livingston
548 CBSS/GBEA
DSN 884-9164
(405) 734-9164
Integrity - Service - Excellence
G
Courtesy of
T56-7 Reliability
Average Time on Wing
EFH(4 Qtr Moving Avg)
ATOW
Inh Goal
Courtesy of
Inh Reliability
1800
1600
1400
1200
1000
800
600
400
200
0
05-2
05-3
05-4
06-1
06-2
06-3
06-4
07-1
ATOW
1009
1061
1023
1045
1053
1117
1372
1439
Inherent Goal
Inherent ATOW
1240
1085
1240
1152
1240
1134
1240
1151
1240
1144
1240
1201
1240
1432
1240
1517
25
Courtesy of
TiN Coated Compressor Blades
Issue
Solution
Eroded blades
reduce power
and surge
margin
Plan
• Incorporate at next depot visit
• Titanium Nitride coating extends
compressor time on wing
• Up to 150% improvement in
dusty/sandy environments
Status as of APR 2007
• Implemented Oct 02
• 1263 compressors produced (43% of fleet
complete)
EB-PVD Coatings
History
•1988 – 1993 Initial Titanium Nitride for commercial application suitable for airfoil
–
–
–
–
erosion - development required for aero engine compressors–
First e-beam PVD (RIC) coating unit for airfoil coating programs.
Military Aircraft Component Improvement Program (CIP) to improve erosion
resistance of GE helicopter engines T64 & T58
CIP program for Rolls-Royce Allison T56 for Hercules C-130 transport
Complete T58-GE-16 compressor set coated and tested for US Navy.
•1994 RIC after three development evolutions, now approved for
aero compressor use :
– alloys include Custom 450, IN 718 and Ti-6Al-4V Alloys
•1996: Allison Engine Company approves Liburdi RIC process for
use on T56 compressor blades
•1997: Rolls-Royce (formerly Allison) begins regular purchasing of
RIC coated T56 airfoils.
•2004: Over 100,000 stage 1 and 2 T56 compressor blades coated
for Rolls-Royce for USAF engines
•2006: AE1107 Engine program approvals
•2008: T56 Series IV
•2008: T55 Army Cargo Heavy Lift program
•2009: PW200 Test Program
•2009: First industrial Fr 7 FA coatings applied
•2010: First industrial Fr 7 FA coatings applied with GEN III
Summary
1. Extending the life of compressor parts through hard
coatings has been proven in service
2. The use of a “Super Polish” combined with a
durable Hard Coat yields maximum performance
and re-establishes surge margins
3. New Generation Corrosion / Erosion coatings marry
the best of both worlds
4. Extending the life of components from 5 to 10 times
their current compressor life expectancy has been
proven over the past decade
11/8/2012
28
Thank You
Please visit with us at Booth 56