When to paint corten B corrosion resistant steel plates

For carbon steel plates or mild steel plates, low alloy steel plates etc., we usually do sand blasting and painting before shipment, so as to protect the steel plates from rusting during long distance transportation and application. However, it is seldom find any steel supplier do painting for corten B corrosion resistant steel.

That because corten B corrosion resistant steel has strong ability against rusting itself. The added Cr, Ni etc alloy elements enable corten B weatherproof steel plates form a protective layer on the surface and go against atmosphere and weather corrossion.

But the self protection is not enough at all. Corten B corrosion resistant steel plate is not adaptable in moisture environment. If the atmosphere is continually wet, corten B corrosion resistant steel plate will not be able to form surface protective layer. For example, when the base of corten B corrosion resistant steel structure is close to the ground or is partially submerged, the corten B corrosion resistant steel plates also need to do painting, so as to protect it from rust.