What Does Surface Preparation Mean?
Surface preparation is the process of treating the surface of a substance in order to increase its adhesion to coatings. The single most important function that influences coating performance is the quality of surface preparation. This can be done mechanically or chemically.
The surfaces most often prepared are:
Surface preparation is also known as grit blasting.
Corrosionpedia Explains Surface Preparation
The surface preparation process is used for clearing a surface of any:
- Pre-existing coatings
- Surface imperfections
- Organic matter
- Other contaminants
Methods of surface preparation include:
- Chemical cleaning (SSPC-SP1): Prior to using any method of surface preparation, it is essential to carry out chemical cleaning, which involves the removal of dirt, oil, grease and other foreign materials with organic solvents or detergents.
- Tool cleaning: This involves two types - hand tool cleaning (SSPC-SP 2) and power tool cleaning (SSPC-SP 3). Loosely adhering mill scale, rust and old paint coatings may be removed from steel by hand wire brushing, sanding, scraping and chipping. However, these methods are incomplete, and always leave a layer of tightly adhering rust on the steel surface. Power tools include rotary wire brushes, sanding discs and needle guns. Power tool cleaning is in general more effective and less laborious than hand tool cleaning for the removal of loosely adhering mill scale, paint and rust.
- High-low or Combinational Pressure Water Cleaning (SSPC-SP 12): Fresh water cleaning is always necessary to remove salts, fouling, any loose paint and other contaminants.
- Abrasive Blast Cleaning (SSPC-SP5 / NACE 1 from SSPC-SP11 / NACE 5): Blast cleaning is based on the principle of an abrasive jet of particles in a compressed air stream impinging on the surface, removing impurities, mill scale, rust and old paint. Abrasive blast cleaning is the most thorough and widely used method of surface preparation in the shipbuilding and repair industry.