EXTERIOR COATING FOR ELEMENT OF UNDERGROUND PIPELINE MANUFACTURED FROM IRON-BASED MATERIAL, COATED PIPELINE ELEMENT AND METHOD OF ABOVE-NOTED SPECIFIC COATING APPLICATION Russian patent published in 2017 - IPC C23C28/00 C23C4/04 C23C4/16 F16L58/04 

FIELD: metallurgy.

SUBSTANCE: exterior coating for an element of an underground pipeline made of an iron-based material, the noted coating has the first porous layer and the second porous layer disposed on the first layer and capable of clogging up the pores of the first layer. The first layer comprises a substantially pure zinc or zinc alloy or a pseudoalloy, the noted alloy or pseudoalloy contains, by weight, at least 50% zinc, and the second layer comprises a single-component water-based paint made from at least one synthetic resin, emulsified, dispersed or dissolved in water. The method for applying an outer coating to said pipeline element comprises the following steps: a) metallizing said first pipeline element with a substantially pure zinc or zinc alloy or a pseudoalloy, the noted alloy or pseudoalloy contains, by weight, at least 50% zinc, and b) applying a second porous layer containing a single-component water-based paint made from at least one synthetic resin, emulsified, dispersed or dissolved in water to the first layer free of white bloom.

EFFECT: effective protection of the pipeline element from corrosion, especially from soil corrosion, with improved sanitary and ecological properties.

22 cl, 1 dwg, 1 ex