INSPECTION LOGBOOK
Coating Inspections - Inspection of Steel Surface Preparation, Part 5 Massimo Cornago NACE International Certified Coating Inspector, NACE CIP PEER Reviewer
F
cornago@ipcm.it
ollowing the previous article, “Inspection of Surface Preparation
White metal blast cleaning (NACE1/SSPC-SP5)
of Steel, Part 4”, and before we discuss other surface preparation
The NACE1/SSPC-SP5 White Metal Blast Cleaning standard states that
systems and their related inspections, beginning with the abrasive
“when viewed without magnification, the surface shall be free of all
blast cleaning process and its related inspection method, let us start
visible oil, grease, dust, dirt, mill scale, rust, coating, oxides, corrosion
by considering the appropriate international standards: NACE, SSPC,
products, and other foreign matter.”
and ISO (the latter of which will be covered in another article). For
Acceptable variations in appearance that do not affect surface
many years, the industry has referred to the NACE and SSPC surface
cleanliness include variations caused by the type of steel, original
preparation standards as if they were exact equivalents, although
surface condition, thickness of the steel, weld metal, mill or fabrication
they actually contained some wording differences. In 1990, the two
marks, heat treating, heat-affected zones, blasting abrasives, and
associations formed a joint task group with the express purpose of
differences due to the blasting technique.
setting joint, identically worded standards for steel abrasive blast
When coating is specified, the surface shall be roughened to a degree
cleaning. Such joint standards were published in October 1994 and
suitable for the specified coating system. Immediately prior to coating
they soon began to be commonly used in the industry at a global level.
application, the entire surface shall comply with the degree of cleaning
Recently, NACE and SSPC have merged and changed their name into
specified. SSPC-VIS1 may be specified to supplement the written
AMPP: Association for Materials Protection and Performance. For the
definition. In any dispute, however, the written standards shall take
time being, however, the standards still maintain the old denomination
precedence over visual standards and comparators.
that we will describe here below.
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N. 40 - 2021 DECEMBER - ipcm® Protective Coatings
