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Levels of
Sandblasting
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SP1 SP5 SP6
SP7 SP10
SSPC SP – 1 (Solvent
Cleaning)
Solvents such as water, mineral spirits,
xylol, toluol, etc., are used to remove solvent-soluble foreign
matter from the surface of ferrous metal. Rags and solvents must
be replenished frequently to avoid spreading the contaminant
rather than removing it. Low-pressure (1500 – 4000 psi) high
volume (3-5) gal./min) water washing with appropriate cleaning
chemicals is a recognized "solvent cleaning" method. All
surfaces should be cleaned per this specification prior to using
hand tools or blast equipment.
SSPC-SP5 (White Metal Blasting)
The removal of all visible rust, mil
scale, paint and contaminants, leaving the metal uniformly white
or gray in appearance. This is the ultimate in blast cleaning. Use
where maximum performance of protective coatings is necessary due
to exceptionally severe conditions such as constant immersion in
water or liquid chemicals.
SSPC-SP6 (Commercial Blast)
All oil, grease, dirt, rust scale and
foreign matter are completely removed from the surface and all
rust, mill scale and old paint are completely removed by abrasive
blasting except for slight shadows, streaks or discolorations
caused by rust stain, mill scale oxides or slight, tight resides
of paint or coating that may remain. If the surface is pitted,
slight resides of rust or paint may be found in the bottom of
pits: at least two-thirds of each square inch of surface area
shall be free of all visible residues and the remainder shall be
limited to the light residues mentioned above.
SSPC-SP7 (Brush-Off Blast)
A method in which all oil, grease, dirt,
rust scale, looses mill scale, loose rust and loose paint or
coatings are removed completely. Tight mill scale and tightly
adhered rust, paint and coatings are permitted to remain. However
all mill scale and rust must have been exposed to the abrasive
blast pattern sufficiently to expose numerous flecks of the
underlying metal fairly uniformly distributed over the entire
surface.
SSPC-SP10 (Near White Blast)
In this method all oil, grease dirt, mill
scale, rust, corrosion products, oxides, paint or other foreign matter
have been completely removed from the surface by abrasive blasting,
except for very light shadows, very slight streaks or slight
discolorations caused by rust stain, mill scale oxides or slight,
tight residues of paint or coating At least 95% of each square inch of
surface areas shall be limited to the light discoloration mentioned
above. From a practical standpoint, this is probably the best quality
surface preparation that can be expected to today for existing plant
facility maintenance work.
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