A REVIEW OF SHOP COATING FAILURE

Renewed attention to the fundamentals of sound application techniques, careful monitoring during application and cure, and well-thought-out coating specifications can prevent many premature coating failures associated with shop-primed steel. This article reviews common causes of failure and the types of failures associated with them. When a primer is applied at insufficient thicknesses and exposed to the environment for several months before topcoats are applied, premature failure may result, manifested as pinpoint rusting. On the other hand, film thicknesses above 5 mils (125 micrometers) are more susceptible to mudcracking, cohesive failure, and ultimately, disbondment. Excessive thickness can also cause solvent entrapment in a primer, which prevents the coating from curing completely. If a surface is contaminated with water-soluble salts and is then primed, the primer may blister badly in the presence of ample moisture. One solution to premature primer failure due to severe or prolonged exposure during the construction phase is to shop apply more than just the primer.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/87551985
• Corporate Authors:

  Technology Publishing Company

  2100 Wharton Street, Suite 310
  Pittsburgh, PA  United States  15203
• Authors:
  • Leyland, D
  • Huntley, R
• Publication Date: 1999-6

Language

• English

Media Info

• Features: Photos;
• Pagination: p. 34-38
• Serial:
  • Journal of Protective Coatings & Linings
  • Volume: 16
  • Issue Number: 6
  • Publisher: Steel Structures Painting Council
  • ISSN: 8755-1985

Subject/Index Terms

• TRT Terms: Blistering; Coatings; Corrosion; Curing agents; Deterioration by environmental action; Failure; Films (Coatings); Primers; Rusting; Solvents; Steel; Structural steel; Thickness
• Subject Areas: Geotechnology; Highways; Materials; I34: Steels and Metals; I35: Miscellaneous Materials;

Filing Info

• Accession Number: 00768879
• Record Type: Publication
• Files: TRIS
• Created Date: Sep 16 1999 12:00AM