Coating considerations for Asset Protection

1. Coating considerations for Asset Protection RINA Conference London Marine Renewable & Offshore Wind Energy 21st - 23rd April 2010 Alan Guy / Rodney Towers Safinah Limited

2. Offshore Wind Energy UK UK Round 3 Wind farm zones • UK target 2020 15% of energy from renewables Estimated that the UK has 33% wind resources in Europe Offshore to be primary expansion zone. Wind is more constant and predictable Jan 2010 • UK govt awards Round 3 wind farm zones / 9 successful bidders £75bn programme for offshore wind farm projects Source: BWEA

3. Offshore Wind Energy UKMW Capacity Plan Source RenewableUK Total Operational Capacity 10 year plan 40,000 MW Largest Offshore Capacity Plan in Europe This is a major growth business sector

4. Offshore Wind Towers Painting Offshore Wind Towers * Source JPCL / Muhlberg March 2010

5. Offshore Wind TowersStructural protection in relation to project costs Typical Wind Tower Structure Factory painting + site erection painting ˂ less than 1% of installed cost

6. Offshore Wind TowersStructural protection in relation to project costs Overview Painting areas & costs If the build specification fails to perform failure repetition can multiply by the number of towers in the field

7. Offshore Wind Tower Fieldsoffshore repairs Coatings unfortunately can fail

8. Offshore Wind Tower Fieldsoffshore repairs Cost Problem Access to offshore location ...not by road ....but ... by boat or barge

9. Offshore Wind Tower Fieldsoffshore repairs Cost Problem Access to repair the coated surface Staging difficult to erect & dismantle

10. Offshore Wind Towers The coating repair cost multiplier Operational cost problem likely to be out of proportion Coating repairs repeat repeat repeat

11. Offshore Wind Towersoffshore repair costs To repair only 3% area failure could cost more than the total initial cost of painting

12. Coating Breakdown • Coating performance failures can occur because of one or more of the following: • Design • Product specification/selection • Product quality • Management processes • Preparation/application • Maintenance • Repairs • Climate/environmental control • Worker skill • Product quality is rarely the cause of failure

13. Coating breakdownproblems for Asset Owner / Field Manager Design, application Specification ? System selection ? Application issues ?

14. Coating breakdownproblems for Asset Owner / Field Manager • Bad spray application • Sharp edges • Stress cracking in dry film Photos ABS, Houston

15. Considerations for achieving long term coating performance Purpose of coating system • Adopt the Functional Specification concept in design phase • Key point – performance 15 - 20 years or 35 - 40 years Choose between • multi layer 3 – 5 coat epoxy / p/urethane system • thermally sprayed Zn/Al + sealer/epoxy topcoats • ‘green’ product 2–3 coat solvent free epoxy system Asset Owner / Field Manager • undertake independent technical evaluation of Paint Specification in Contract proposal prior to Contract agreement

16. Offshore Wind Towers three different environmental zones Upper section - atmospheric blades, turbine, housings & structure Coating - durable, anti-corrosive Lower section – splash / tidal tower structure Coating - durable, anti-corrosive Bottom section– tidal/immersed/buried tower structure Coating - anti-corrosive, anti-fouling Splash zone is the most critical

17. Offshore Wind Towers Coating selection • Structures similar to rigs, platforms and ships • Difference unmanned difficult to monitor/assess • Requirements long term performance suitable for fabrication process suitable for range of environment ease of repair • Needs care in selection quality application

18. Offshore Wind Towers Coating selection • Principal methodology ISO 12944-2 • Defines corrosion category of site by rate of steel loss • Combine category with required durability to select generic coating schemes • Non-immersed areas C5-M applies • Immersed areas Im-2 applies • ISO 20340 further defines requirements for high durability systems

19. Offshore Wind Towers Coating selection Generic 15 year maintenance free systems Coastal / offshore areas with high salinity sea or brackish water schemes selected should have proven track records in the field

20. Offshore Wind Towers Coating system for 30-40 years protection Metallizationhas now achieved 30 – 40 years low maintenance protection on offshore oil & gas structures • The cost and application speed for systems which include this process are now close to or the same as for multi layer organic coating systems • The reasons are a combination of New alloy materials New technology spray equipment Contractors improved ability to control the application environment • The current trend in Europe is to thermally spray Zn / Al (first coat) 60 – 100 mic dft + sealer coat + 2 x EP topcoats Full exterior surface and internally 6-8 m up from bottom

21. Painting Wind Towersthe importance of quality application The application contractor controls about 75-85% of the cost The importance of good application is fundamental for success Best Quality Application requires • Specified Standards of secondary surface preparation for steel & appropriate QC • Trained and skilful spray painting personnel • Applicators to conduct own DFT & QC work for multi layer coating systems • Applicators to have control over environmental conditions during the application process

22. Painting Wind Towersfor long term coating performance Optimum approach Purpose built Wind Tower coating factory Photo Muehlhan Herning, Denmark

23. Painting Wind Towersfor long term coating performance • Series of blasting & coating cells • Auto blasting / more consistent Rz and surface cleanliness • Some robot painting / internals • Two component spray equipment • Dust free environment • Climate & temperature regulation • Relative Humidity control Photo Muehlhan GmbH

24. Painting Wind Towersfor long term coating performance Spray application epoxy / p/urethane multi layer systems or topcoats Photo Muehlhan GmbH

25. Painting Wind Towersfor long term coating performance Thermal spraying Zn / Al alloy metallization Photo Muehlhan GmbH

26. Painting Wind Towersfor long term coating performance Finish painting internal areas Photo Muehlhan GmbH

27. Wave & Tidal devicesPrototype design - testing – scaling up Some differing environmental conditions But same considerations for long term coating performance

28. Offshore Marine Renewablesimpact of fouling Wind Towers • will occur but impact on power generation and coating performance generally small • will be confined to tidal & immersed areas Wave & Tidal devices Impact could be significant. Issues may be • how to minimise fouling adhesion • differences between exposed surfaces steel & composite materials static or moving • possible impact of greater hydrodynamic loads on tethered devices from fouling build up

29. Offshore Marine Renewablestidal devices In locations of ‘useful’ tidal range and flow, abrasion resistance of coatings and materials may be an issue

30. Coating Considerations for Asset Protection & Structural Integrity Coating product quality failures are unusual. Specification failures are not • Three recommended actions for Client / Asset Owner / Field Manager which can reduce risk 1. Apply the Functional Specification approach Coating system suitability for performance requirement Coating system suitability for the application process Coating system suitability for the field environment Coating system suitability for repair & maintenance 2. Make an independent technical evaluation of coating specification within design phase and prior to Build Contract 3. Audit the coating process independently during construction phase • Post ISO 9000 wrong coating specification cases have doubled ! * * Source JPCL / K.Muhlberg Mar 2010

31. Unmanned structures ...deserve wise protection !

32. Sources & References Sources of info & Photos • NaREC, Blyth, Northumberland • EMEC, Stromness, Orkney • Muehlhan GmbH, Hamburg • ABS, Houston Papers • K.Muhlberg / JPCL March 2010 ‘ Corrosion Protection of Offshore Wind Turbines’ • A. Momber / JPCL Apr 2008 & Apr 2009 ‘ Investigating Corrosion Protection of Offshore Wind Towers Parts 1 & 2 ’ ‘ Thank you ‘