3520Zinc-Rich Paint Systems

3520.1SCOPE

Provide zinc-rich paint systems.

A Zinc-Rich Primer A.1 General Provide multi-component zinc-rich primer capable of being spray-applied in accordance with the manufacturer’s instructions and applications guide. After mixing according to the manufacturer’s recommendation, strain the primer through a 30-60 mesh screen or a double layer of cheesecloth to remove un-dispersed zinc agglomerates. Formulate the primer to produce a distinct contrast with blast cleaned steel and with the subsequent intermediate coat. A.2 Pigment Provide a metallic zinc pigment meeting the requirements of ASTM D520, Standard Specification for Zinc Dust Pigment. Only add inert Materials to the pigment for tinting. Ensure the inert Materials do not reduce the effectiveness of the galvanic protection. A.3 Finished Primer Provide finished primer meeting the requirements in Table 3520.2-1: Table 3520.2-1 Finished Primer Requirements Characteristic Requirement Zinc portion, total solids by weight ≥ 75.0 percent Pot life at 77°F ≥ 4 hour Density of VOC ≤ 3.5 pounds/gal Slip coefficient of cured primer ≥0.33 Cure time for recoating* per Manufacturer’s Product Data Sheet * When applied at 3 mil dry-film thickness at 77°F and 50 percent R.H. B Approved Zinc-Rich Systems Provide a zinc-rich paint system listed on the the APL, Bridge, “Bridge structural steel coating” B.1 Organic Zinc-Rich Epoxy System Provide a zinc-rich epoxy system consisting of a zinc-rich epoxy primer, an epoxy intermediate coat, and an aliphatic urethane finish coat. B.2 Inorganic Zinc-Rich System Provide an inorganic zinc-rich system consisting of solvent based inorganic zinc-rich primer, an epoxy intermediate coat, and an aliphatic urethane finish coat . B.3 Moisture Cure Zinc-Rich System Provide a moisture cure zinc-rich system consisting of moisture cure zinc-rich primer, a urethane intermediate coat, and an aliphatic urethane finish coat . B.4 Two Coat Zinc-Rich System Provide a zinc-rich system consisting of either a moisture cure zinc-rich primer or an organic zinc-rich epoxy primer and a fast dry polyaspartic urethane finish coat . C Color Provide a semi-gloss finish coat as required by the Contract.

D Packaging and Labeling Provide multi-component paints packaged in separate containers or kits that ensure paint manufacturer’s mixing proportions are achieved when using the entire container.

3520.3SAMPLING AND TESTING

Provide to the Engineer a manufacturer’s Certificate of Compliance with each batch, lot, or both for each component of the zinc-rich paint system. Provide a color draw down sample on a Leneta chart per ASTM D2805, Standard Test Method for Hiding Power of Paints by Reflectometry, to the Materials Laboratory for verification of the finish coat color using the requirements and measurement conditions found in 3501.2B, “Colors.”