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Centre for Research in Engineering and Surface Technology. John Colreavy Enterprise Ireland Restoration of the Ha’penny Bridge. Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004. Restoration of the Ha’penny Bridge
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Centre for Research in Engineering and Surface Technology John Colreavy Enterprise Ireland Restoration of the Ha’penny Bridge Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Introduction • A little Irish History. • Paint specification and resultant issues. • Performance evaluation. • Surface preparation and soluble salts. • Harland & Wolff facilities. • Railings assembly. • Importance of supervision and inspection. • Summary. Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge History • Officially opened in 1816 and named Wellington Bridge (Iron Bridge after the Iron Duke). • Cast at Coalbrookdale in Shropshire. • Only pedestrian bridge up to 2000. • Erected by Alderman Beresford at a cost of £3,816.11s.6d. • Mr William Walsh ordered to replace his unworthy ferry fleet by Dublin Corporation. Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Performance expectations • ISO 12944 Paints and Varnishes – Corrosion Protection of Steel Structures by Protective Paint Systems. Part 1. General Introduction Part 2. Classification of Environments. Part 3. Design Considerations. Part 4. Types of Surface and surface preparation. Part 5. Protective Paint Systems. Part 6. Laboratory Performance Test Methods. Part 7. Execution and supervision of paint work. Part 8. Development of specifications for new work/ maintenance. C4 Environment Industrial Areas and coastal areas with moderate salinity. Chemical plants, swimming pools, coastal shipyards. Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Paint specification PerformanceNo Maintenance up to 12 years Minor maintenance from 12 years Major maintenance after 20 years Existing cast iron bridge superstructure Zinc phosphate 2 pk. epoxy blast primer 12m2/litre Zinc phosphate high build quick drying 2 pk. epoxy primer dft 100m High build MIO high build quick drying epoxy undercoat dft 125m High build MIO high build quick drying epoxy undercoat dft 125m Acrylic Urethane finish. dft 50m New steel sub-frames to walkway (Decks)/New ductile iron handrail/New steel bracing members Aluminium metal spray Zinc phosphate 2 pk. epoxy sealer 12m2/litre High build MIO high build quick drying epoxy undercoat dft 125m High build MIO high build quick drying epoxy undercoat dft 125m Acrylic Urethane finish. dft 50m Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Specification issues. • Removal of aluminium metal spray advised. • Galvanising advised for walkway sub-frames/new steelwork. • Specification for sealers/stoppers and fillers. • Specification for in-fill bars and joint sealers. • SA2½ adequate. • Chilled iron grit to be avoided. • J-Blast/Garnet or alumina preferred (J-blast for lead removal) • Wet abrasive blast existing lead to reduce airborne hazard. • Penetrating blast primer to facilitate crevice protection. • Second finish specified as final operation. . • Colour match flakes removed from existing paint system Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Performance Evaluation Type approval DescriptionStandard Neutral salt spray ISO 7253 >720 hours Condensation ISO 6270 >480 hours Blistering ISO 4628-2 0 Rusting ISO 4628-3 Ri0 Cracking ISO 4628-4 0 Flaking ISO 4628-5 0 1700 hours without defects achieved in salt spray. Existing track record on Turner Curvilinear Greenhouse in Gardens. Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
3.6 metres 42.8 metres 6 sections 7.2 metres long. 12 deck panels. 20 railing panels. Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Soluble salts Dublin Existing Trusses Lead gaskets End-caps Diaphragms Cast porosity Fish-belly beams. Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Soluble Salts Oxidation M M+ + e (metal loss at anode). Reduction O2 + 2H2O + 4e 4OH-(oxygen reduction at cathode) M++Cl-+H2O = MOH +H+Cl- Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Soluble Salts Rib section lug Rib section lug K3FE(CN)6 K3Fe(CN)6 before hydroblasting after hydroblasting Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
End-caps Fish-belly beams End-cap sockets Dublin Existing Trusses Cross-member joints Diaphragms Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Harland & Wolff Environmental Cell Paint Cell Variable control for the most vulnerable component. Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Harland & Wolff Titanic Engine Room Paint Cell Decks 9 - 12 Harland & Wolff Drydock Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Railings Disassembled railings at H&W Panel layout at GHC Dromore Railing restoration logistics Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Railings Assembly on-site Final fix with marine engine epoxy Competing operations Final inspection Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge Inspection Consultation • Advice on specification (ICorr network) • Type approval. • Compatability evaluation. • Trouble-shooting(ICorr network) Inspection Compilation of project QA records. Monitoring Substrate cond. SA2½ etc. Environmental conditions Dew point, temperature etc. System dft’s eddy current. Paint QA/S.G. Approval system. Production versus inspection! Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge • Trusses • Soluble salts and hydro-blasting • Complex structure requiring sealers and bedding compounds. • Treatment of porosity • Decks • Aluminium metal spray not appropriate. • Box-sections flooded • Benefits of shipyard facilities. • Consult corrosion consultants at design stage • Railings • Logistics • Soluble salts • Competing operations Advances in Corrosion Protection by Organic Coatings Christ’s College Cambridge 20th to the 24th of September 2004
Restoration of the Ha’penny Bridge The Final Product Nostrada Restoration Award September 8th Lord Mayor Ryan Thank You