Surface finish

Surface treatment of forge-welded gratings

Steels S235JR, S355JR

  • mill finish, without surface treatment
  • hot-dip galvanized according to EN ISO 1461
  • powder coated – RAL shades

Excerpt from EN ISO 1461
Minimum thickness of zinc coating on steel

Steel material thickness
t
[mm]
Local coating thickness
(minimum)
 [μm]
Average coating thickness
(minimum)
 [μm]
t < 1.53545
1.5 ≤ t ≤ 34555
3 < t ≤ 65570
t > 67085

Excerpt from EN ISO 9223
Atmospheric corrosivity categories

CategoryCorrosivityCorrosion loss
steel [μm/year]
Corrosion loss
zinc [μm/year]
C1Very lowless than 1.3less than 0.1
C2Low1.3 to 250.1 to 0.7
C3Medium25 to 500.7 to 2.1
C4High50 to 802.1 to 4.2
C5Very high80 to 2004.2 to 8.4
CXExtreme200 to 7008.4 to 25