{"id":25653,"date":"2018-02-07T21:48:29","date_gmt":"2018-02-07T21:48:29","guid":{"rendered":"http:\/\/www.newsteelconstruction.com\/wp\/?p=25653"},"modified":"2018-02-09T10:54:51","modified_gmt":"2018-02-09T10:54:51","slug":"an-introduction-to-surface-preparation-for-corrosion-protection","status":"publish","type":"post","link":"https:\/\/www.newsteelconstruction.com\/wp\/an-introduction-to-surface-preparation-for-corrosion-protection\/","title":{"rendered":"An introduction to surface preparation for corrosion protection"},"content":{"rendered":"
\"\"

Galvanized steelwork is used in numerous industrial applications such as supporting silos, as pictured<\/p><\/div>\n

Cost-effective corrosion protection of structural steelwork can be achieved through the appropriate application of paint and metallic coatings and should present little difficulty for common applications and environments if the factors that affect durability are recognised at the outset.<\/h4>\n

In this article NSC looks at surface preparation which is the essential first stage treatment of a steel substrate before the application of any coating, and is generally accepted as being the most important factor affecting the total success of a corrosion protection system.<\/p>\n

Why surface preparation is essential to ensure effective corrosion protection?<\/strong><\/span>
\nThe performance of a coating is significantly influenced by its ability to adhere properly to the substrate material. The initial surface condition<\/a> of steel can vary in terms of the amount of residual millscale and degree of initial rusting. However, generally it is an unsatisfactory base upon which to apply modern, high performance protective coatings.<\/p>\n

Preliminary treatments<\/span><\/strong>
\nResidues of oil, grease, marking inks, cutting oils etc. after fabrication operations will seriously affect the adhesion of applied coatings and must be removed. It is erroneous to think that subsequent cleaning operations will remove such contaminants and it is bad practice to permit them to remain on the surface. Failure to remove these contaminants before blast cleaning<\/a> results in them being distributed over the steel surface and contaminating the abrasive. Suitable organic solvents, emulsion degreasing agents or equivalents should be applied to remove contaminants in preparation for subsequent descaling treatments.<\/p>\n

Blast cleaning<\/span><\/strong>
\nA range of methods of preparation and grades of cleanliness exist, but by far the most significant and important method used for the thorough cleaning of millscaled and rusted surfaces is abrasive blast cleaning.<\/p>\n

The standard grades of cleanliness for abrasive blast cleaning in accordance with ISO 8501-1 are:<\/p>\n