SCS技术

Smooth clean surface (SCS) is a process applied to hot rolled sheet metal and coils
to remove nearly all mill scale and clean the steel surface.

The SCS process feeds hot rolled sheet steel, either as individual blanks or as a continuous strip
that is uncoiled, into the SCS "brushing machine".

Within the machine the steel is passed between sets of rotating roller brushes that
spin on an axis perpendicular to the sheet*s direction of travel. The roller brush exterior
is an engineered abrasive, similar to Scotchbrite, that makes contact with the steel
under pressure. Each roller brush spins against the steel at a speed of 900 to 1000
revolutions per minute, "scrubbing away" the outer layers of mill scale – hematite
and magnetite – and most of the inner layer, wustite.

The SCS process imparts a measure of rust resistance to the sheet steel,
so that when exposed to a noncondensing atmosphere, its propensity to rust
is markedly less than that of hot rolled steel that is not treated with the SCS
process. The exact metallurgical phenomenon underlying this transformation
of the surface to make it more rust resistant is not fully understood; however,
it is theorized that the remaining wustite layer (chemical symbol FeO)
contains a much lower proportion of oxygen than the removed hematite
and magnetite layers and is, therefore, more stable and less prone to
oxidation when exposed to a noncondensing atmosphere.

The SCS process and its attendant equipment is now paired with a related process,
eco pickled surface or EPS. The EPS technology accomplishes a more complete removal
of surface oxides than does the SCS process; however, it can also leave the surface
with an overall rougher texture, as indicated by Ra or roughness average. The SCS process
is applied directly after the EPS process to produce a smoother surface when desired.

Roll brushes shown inside the SCS brushing machine.