feet and does not require a surface profile, chemi-
cal stripping may be cost-e;ective; conversely, if
there are several thousand square feet of surface to
be prepared, pickling or abrasive blasting would be
Whether or not the waste produced would need
to be disposed of as hazardous has an e;ect on the
methods used as well.
“The customer will give the fabricator a build
sheet, if you will,” Berish said. “’We want it to be
fabricated like this: the bolts located here, with this
diameter.’ It’s the same with the surface condition.
Just by the material they’re going to use, they’re
going to go to that material data sheet that will tell
what surface standard is compatible with that material—SP 1, SP 2 or 3, SP 6 or SP 10.”
SSPC-SP 1: Solvent Cleaning
The first line of defense is simply cleaning the structural member with acetone, a thinner, or another
type of solvent.
“Cleaning with a solvent and a cloth is a precursor to every other surface preparation standard out
there. It’s a given,” Berish said.
Cortec® Technical Service Engineer John Wulter-
kens said that fabricators can remove mill scale, ox-
ides, and corrosion from the metal surface using ei-
ther VpCI®-422 or VpCI-426 water-based liquids (see
Figure 2). “VpCI-422 is more ‘ecofriendly’ (biode-
gradable); VpCI-426 is stronger and works faster. De-
pending on the application, the gel versions of both
products can be used on vertical or overhead surfac-
es, or on parts that cannot be treated in a dip bath.”
A;er the scale is removed, cleaning and neutral-
ization should be performed with a water-based al-
kaline cleaner, he added. “This will leave behind a
cleaner surface for painting, coating, and welding.
The cleaners (and rust/oxide/scale removers) con-
tain flash corrosion inhibitors, so a;er the neutraliza-
tion and cleaning stage, the surface will remain flash
rust-free for up to a week, depending on conditions.”
SSPC 2, SSPC 3:
Hand Tool, Power Tool Cleaning
Bass Mechanical, a structural steel fabricator in
Elizabethtown, Pa., has 40- by 80-foot drive-through
bays that handle both medium- and large-scale
structural steel fabrication. The company fabricates
and welds carbon steel, aluminum, stainless, and
nickel aluminum into trusses, box girders, plate
girders, beams, columns, mezzanines, stairways,
Before sending its products out for coating, the
company performs some minimal surface prep,
according to Jerry Miller, chief operations o;icer.
“We usually go to an SSPC-SP 2 or SP 3, which
requires the steel to be free of grease, moisture,
contaminants, heavy mill scale, and rust.” Miller
said the company uses a thinner and a power tool
to remove the contaminants. Then it uses high-
pressure air to blow the dirt or dust and rust away,”
Standards SP 2 and SP 3 require the use of a hand
or power tool to satisfy the requirement, Berish
said. “By standard, SP 2 means that the surface is
clean of all oils and loosely inherent material. So SP
2 is hand cleaning with the use of hand tools—a wire
brush or a scraper. The use of a chemical treatment
alone cannot make it an SP 2 because you cannot
remove inherent materials with chemicals alone.”
SP 3 is the standard for cleaning and removing
loosely inherent material using a power tool, such
as a grinder (see Figure 3).
The SSPC’s surface preparation’s standard name indicates the method used, and all surface preparation
standards use the prefix SP.
At le; is a metal surface with corrosion removed using VpCI®-422; at right, a metal surface before the corrosion was
removed. Photos courtesy of Cortec Corp., St. Paul, Minn.
SSPC-SP 3 is the standard for cleaning and removing loosely inherent material using a power tool, such as a grinder. Photo courtesy of Bass Mechanical, Elizabethtown, Pa.