Sand Blasting

Sand Blasting

Sand blasting is majorly used for the  surface preparation of steel surfaces, Storage tanks & Pressure Vessel. Sand blasting removes rust, existing coatings, mill scale, dirt, oil, grease, and other contaminants. It creates an anchor pattern for the primer.

Sandblasting required newly manufactured or repainted steel to be pressure washed or steam cleaned

All paint specifications that are provided with sandblasting requirement should specify the type of blast required. Following are standards for the degree of cleanliness of the sandblasted steel substrate
•    NACE (National Association of Corrosion Engineers)
•    SSPC (Steel Structures Painting Council)
•    Sa (Swedish Pictorial Standards).

White Metal Blast": NACE 1, SSPC-SP5, or Sa 3:
It produces steel surfaces which when viewed without magnification shall be free of all visible grease, oil, dust, dirt, mill scale, coatings /paint and rust. Sand or grit used in sand blasting is graded as MESH SIZE. (mesh size 16 - 30) is  used because of its productive & aggressive removal potential. This particular mesh size sand can create a profile on steel as high as 3.5 - 4.0 mils.

Near White Metal Blast": NACE 2, SSPC-SP10, or Sa 2 1/2:
It produces  steel surfaces which  when viewed without magnification shall be free of all visible grease, oil, dust, dirt, mill scale, coatings /paint and rust. Stains of rust & mill scale, and stains of previously applied paint may remain not  upto 5-6% of the surface.

Commercial Blast”: NACE 3, SSPC-SP6, or Sa 2:
It produces  steel surfaces which  when viewed without magnification shall be free of all visible grease, oil, dust, dirt, mill scale, coatings /paint and rust. Stains of rust & mill scale, and stains of previously applied paint may remain not  upto 33-35% of the surface.

Brush Off Blast Cleaning: NACE 4 / SSPC-SC7 / Sa 1:
It produces  steel surfaces which  when viewed without magnification shall be free of all visible grease, oil, dust, dirt, loose mill scale, coatings /paint and rust. The remaining mill scale, rust or paint must remains tightly sticked so that surface has sufficent affinity to provide better bonding and adhesion to a dedicated paint system.

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