| Protective Coatings Structures shall be galvanized unless
otherwise noted.
Galvanizing shall be performed in accordance with the following
specifications:
ASTM A123 - Standard Specification of Zinc (Hot Dipped
Galvanized) Coating on Iron and Steel Products
ASTM A143 - Standard Practice for Safeguarding Against
Embrittlement of Hot-Dip Galvanized Structural Steel Products and
Procedure for Detecting Embrittlement
ASTM A153 - Standard Specification for Zinc Coating (Hot-Dip) on
Iron and Steel Hardware
ASTM A376 - Standard Practice for Measuring Coating Thickness by
Magnetic-Field or Eddy-current (Electromagnetic) Test Methods
ASTM A384 - Standard Practice for Safeguarding Against Warpage
and Distortion During Hot-Dip Galvanizing of Steel Assemblies
ASTM A780 - Repair of Damaged and Uncoated Areas of Hot-Dip
Galvanized Coatings
All drilled and tapped holes and nuts welded to tubular assemblies
will be retapped with the proper oversized tap after galvanizing.
No double dipping is ever performed.
Anchor Bolts are Galvanized a minimum of 18 inches.
When structures are too large or difficult to galvanize, metalizing
is often the preferred coating substitute. This method employs the
thermal spraying of the base metal using a zinc wire with a minimum of
99.9% purity. Prior to flame spraying, the surface is blasted to a
"white metal" as described in the Steel Structure Painting
Council Specification.
Metalizing shall be preformed in accordance with the American
Welding Society Publication C2.2-67, "Metalizing with aluminum and
Zinc for Protection of Iron steel."
Structures to be painted shall be cleaned after fabrication in
accordance with the applicable
Steel Structure Painting
Council specifications and in strict accordance with the paint manufacturer's
recommendations.
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