5-94 When random DFT testing of a large quantity of small parts and/ or secondary framing members results in unacceptable DFT’s, the Contractor shall hav e the option of measuring and documenting the DFT of each piece or removing the coating a nd/or recoating all pieces represented in the production lot.
506.16 Touch-up and Repairs Touch-up is the repair of minor bl emishes, including but
not limited to, scratches and abrasions that to do not penetrat e underlying layers of coating. Perform touch-up using the same coating and methods specified i n the Manufacturer's Product Data Sheet. Cure the touch-up coating in the same mann er as the original coating. Repair coating damage that penetrates underlying layers in acco rdance with the Manufacturer's Product Data Sheet and this Specification. Prep are areas to be repaired in a manner that assures the proper adhesion of each coat. Feather back each damaged layer so that each repair coat is continuous with each corresponding exi sting coat. The topcoat shall be smooth and uniform in appearance. Repair damaged or unaccep table shop coating before the piece is removed from the paint area.
506.17 Handling and Storage Handle coated members in a manner that avoids damage
to the coating. Lift and move members using non-metallic sling s, padded chains and beam clamps, softeners or by other non-injurious methods. Store pai nted material in a manner that prevents damage to the coating. Document damage to the coating t hat is discovered after the pro duct is loaded for shipment to the job site. Minor damage as a result of handling shall be considered field repair unless, in the opinion of t he Fabrication Engineer, the damage is the result of negligence or poor handling methods. Damage that is deemed to be the result of negligence or poor handling methods shall be repaired as directed by the F abrication Engineer.
506.18 through 506.19- Reserved
HOT-DIP GALVANIZING
506.20 Description This work shall consist of surface preparat ion and application of
hot-dip galvanizing in accordance with the Plans and this Speci fication. Hot-dip galvanizing shall meet the requirements of AASHTO M111/ASTM A123, Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel (A123), including any applicable requirements listed in Section 2-Referenced Docu ments. The minimum average coating thickness grade shall conform to Table 1. The frequency of testing shall be in accordance with Section 6. The choice of the test method is the prerogative of the Contractor. Record the test re sults and provide them to the De partment. Provide certification of compliance and written test results to The Dep artment in accordance with A123 -Section 10. 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.