5-95
506.21 Surface Preparation Abrasive blast-clean the steel to a minimum of SSPC-SP 6,
Commercial Blast Cleaning (SP6) prior to galvanizing. Grind all corners exposed in the assembled product to a 1/16 inch radius prior to galvanizing.
506.22 Repairs Repairs to galvanizing shall be in accordance w ith ASTM A780,
Standard Practice for Repair of Damaged and Uncoated Areas of Hot-Dip Galvanized Coatings (A 780), Annex A1 or A3. Zinc-rich paints for repairs may only be used with approval of the Fabrication Engineer.
506.23 Top-coating Galvanized Surfaces Areas of galvanized sur faces to be top-coated
will be described on the Plans or in the Special Provisions. Do not use chromate quenching or other types of quenching after galvanizing. Remove runs, sags, dross and other deleterious material from surfaces to be painted. Provide a smooth uniform surface, free of heavy build areas or other disc ontinuities that will project through the finish coat. Perform repairs to galvanizing in acc ordance with A 780. Remove visible surface contaminants in accordance with SSPC-SP 1, Solvent Cleaning (SP 1) prior to blast cleaning. Blast-clean surfaces to be coated in accord ance with SSPC-SP 7/NACE No.4-Brush-Off Blast-Cleaning (SP 7). Measure the anchor profile in accordance with ASTM D4417 Method C (replica tape). Record the results in a manner acceptable to the Fabrication Engineer. Assure that the anchor profile correspond s with the anchor profile requirements on the Manufacturer's Product Data Sheet.
506.24 Materials Provide materials in accordance with 506.11.
506.25 Mixing and Application Mix and apply in accordance with 506.14.
506.26 Dry Film Thickness Measure and record the DFT in accord ance with 506.15.
506.27 Touch-up and Repairs Perform touch-up and repairs in ac cordance with 506.16.
506.28 Handling and Storage Handle and store material in accor dance with 506.17.
506.29 Reserved
THERMAL SPRAY COATING
506.30 Description This work shall c onsist of surface preparat ion and application of
Thermal Spray Coatings (TSC) i n accordance with the Plans and t his Specification. Application of TSC to steel subs trate shall be done in accordan ce with requirements, recommendations and appendices of the current Joint Standard AASHTO S8.2:Specification for the Application of Thermal Spray Coating Systems to Steel Bridges (The Standard) and this Specification. The applicator shall provide c opies of application procedures, operator qualifications, QC Manuals and repair procedures.