Wind Turbines: Challenges Associated with Corrosion Protection.
-
Upload
amice-morrison -
Category
Documents
-
view
227 -
download
2
Transcript of Wind Turbines: Challenges Associated with Corrosion Protection.
![Page 1: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/1.jpg)
Wind Turbines: Challenges Associated with Corrosion Protection
![Page 2: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/2.jpg)
Learning Outcomes• At the conclusion of this webinar you will be
able to:– Define the coating-specific sections– Define challenges associated with corrosion
protection of wind turbines– Define wind turbine performance standards– Define corrosion protection methods for
wind turbines– Define industry standards for corrosion
protection of wind turbines– Define coating systems used to protect wind
turbines
![Page 3: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/3.jpg)
Two Wind Markets – Onshore and Offshore
![Page 4: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/4.jpg)
Three Coatings Sections - Onshore
Rotor Blades
Nacelle
Tower
![Page 5: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/5.jpg)
Five Coatings Sections – Offshore
Rotor Blades
Nacelle
Tower
Substructure
Mooring
![Page 6: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/6.jpg)
Challenges in Corrosion Protection of a Wind Turbine• Most wind farm owners/operators
are looking for a 20-25 year service life on all coatings.
• In general, coating manufacturers and tower fabricators may be asked to provide a joint warranty for a specific time frame
![Page 7: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/7.jpg)
Challenges in Corrosion Protection of a Wind Turbine – Onshore • Wind turbines are
usually placed in rural, often remote areas, making future maintenance challenging and expensive
• Wind turbines can stretch hundreds of feet in the air, making accessibility difficult
![Page 8: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/8.jpg)
Challenges in Corrosion Protection of a Wind Turbine – Onshore • On-Shore Wind Turbines
face the following challenges:– Dew/condensation with
or without salinity– Exposure to UV light– Wind blown debris– Extreme temperature
ranges• 130 F (54 C) to -80F
(-62 C)
![Page 9: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/9.jpg)
Challenges in Corrosion Protection of a Wind Turbine – Offshore • In addition to the
previous challenges, off-shore wind turbines face:– Mechanical loads
• Floating Ice• Biofouling in
Submerged Zones– Variation in Weather
Conditions• Wind and Waves
![Page 10: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/10.jpg)
Rotor Blades Performance Standards• Coated rotor
blades must be free of imperfections. Each surface imperfection on a wind turbine blade results in additional drag, and thus, decreases efficiency
![Page 11: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/11.jpg)
Rotor Blades Performance Standards• Rotor blades flex when in use,
therefore so must there protective coatings– Coatings must flex without fracturing– Coating must be able to retain
adhesion to the base coat and substrate when rotor blades flex
![Page 12: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/12.jpg)
Rotor Blades Performance Standards• Coatings applied
to Rotor Blades must be abrasion resistant. With Rotor Blades up to 5 MW (mega watts) being installed, they are susceptible to wind blown debris
![Page 13: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/13.jpg)
Nacelle Performance Standards
• The nacelle must be protected from corrosion using a protective coating system
• The inside must be kept clean and dry. Climate is controlled using dehumidifiers
![Page 14: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/14.jpg)
Tower Section Standards• The tower consist of three sections:
– Steel Tower which is protected with a coating
– Sub-Structure of the tower if sub-merged in water is protected by cathodic protection in conjunction with a coating system. If on-shore just a coating system is necessary
– Mooring is protected with a coating
![Page 15: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/15.jpg)
Tower System Requirements
• ISO 12944 deals with performance requirements for protective paint systems– Defines test methods used to
determine the composition of the separate components of the paint systems
– Defines laboratory performance test methods for assessing the paint systems
– Defines criteria for evaluating results
![Page 16: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/16.jpg)
Tower System Requirements
• Typical evaluation criteria is:– Degree of blistering and cracking
(ASTM D 714 or ISO 4628)– Degree of rusting (SSPC VIS 2, ASTM D
610 or ISO 4628)– Degree of chalking (ISO 4628)– Degree of flaking (ISO 4628)– Adhesion (ASTM D 4541 or ISO 4624)
![Page 17: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/17.jpg)
Tower System Requirements
• Creep from scribe after 4200 hours of exposure to stresses of:– UV Light– Condensation– Salt Spray– Freezing– Immersion in Sea Water (ISO 2812)
• Cathodic disbonding after 4200 hours per ISO 15711
![Page 18: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/18.jpg)
Tower System Requirements• ISO 12944 defines five corrosion
categories:– C1 (not corrosive interior atmosphere)
up to C5-I and C5M (Industrial and Marine)
– Most wind farms are rural areas, C3 (Moderate Load)
– According to Part 5, C3 categories should be coated with a multi-coat system with a DFT of 6-10 mils
![Page 19: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/19.jpg)
Tower System Requirements
• ISO12944 Part 5 defines expected time of protection for various coating systems
• Low Durability– (2 to 5 years)
• Medium Durability – (5 to 15 years)
• High Durability – (greater than 15 years)
![Page 20: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/20.jpg)
On-Shore Typical Coating Systems• Three Coating System
– Epoxy Zinc-Rich Primer (2 to 4 mils)– Epoxy Intermediate Coat (4 to 6 mils)– Polyurethane Topcoat (2 to 4 mils)
• High Performance Two Coat Systems– Epoxy Zinc-Rich Primer (3 to 4 mils)– Polyurethane Topcoat (4 to 5 mils)
![Page 21: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/21.jpg)
Off-Shore Corrosion Protection
• Standards for off-shore wind turbine protection are:– ISO 12944– NORSOK M 501
![Page 22: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/22.jpg)
Off-Shore Corrosion Protection
• ISO 12944 characterizes the conditions to which offshore wind turbines are exposed to as C5 M or IM 2 (immersion)
• C5 M categories are non-immersed and should be coated with a multi-coat system with DFTs in the range of 12 to 20 mils
• IM 2 indicates structure is immersed and should be coated with a multi-coat system with DFTs in the range of 20 to 40 mils in conjunction with cathodic protection
![Page 23: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/23.jpg)
Off-Shore Corrosion Protection
• NORSOK M-501 specifies similar systems
• Atmospheric exposure should have a minimum DFT of 13 mils
• Immersed exposure should have a minimum DFT of 18 mils
![Page 24: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/24.jpg)
Typical Off-Shore Above Splashzone Coating Systems• Three Coating System
– Epoxy Zinc-Rich Primer (2 to 4 mils)– Epoxy Intermediate Coating (2 Coats at
4-6 mils)– Polyurethane Topcoat (2-4 mils)
![Page 25: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/25.jpg)
Typical Off-Shore Under Splashzone Coating Systems• Two Coat System
– Epoxy Coating (2 coats at 8-10 mils)
• NOTE- For areas under water (immersion service) NORSOK requires cathodic protection to be used in conjunction with coating system– Install impressed cathodic corrosion protection– Weld sacrificial anodes
![Page 26: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/26.jpg)
Looking Ahead• Self repairing coatings
– Healing agents/inhibitors release from microcapsules when coating gets damaged
![Page 27: Wind Turbines: Challenges Associated with Corrosion Protection.](https://reader035.fdocuments.in/reader035/viewer/2022070406/56649dde5503460f94ad69f1/html5/thumbnails/27.jpg)
Summary• Coating wind turbines can be
challenging due to the complicated design of the structure and environmental location. To assure corrosion protection, industry standards must be followed and qualified coatings applied.