| 摘要 |
The invention relates to an outer coating (9) for an underground piping element (7) made from iron, in particular cast iron, the outer coating having a first porous layer (11) and a second porous layer (13) positioned on the first layer and able to plug the pores of the first layer, the outer coating being characterized in that: the first layer includes a substantially pure zinc or a zine alloy or pseudo-alloy, the alloy or pseudo-alloy including, in terms of mass, at least 50% zinc, preferably between 0.5% and 40% aluminum, and the second layer comprises a one-component paint in the aqueous phase made from at least one synthetic resin emulsified, dispersed or dissolved in water. The invention also relates to a corresponding coated piping element and method for depositing the coating. |
