ISO 8179-2:2017 pdf free
ISO 8179-2:2017 pdf free.Ductile iron pipes, fittings, accessories and their joints一External zinc-based coating
The zinc-rich paint coating shall cover the outside cylindrical surface of the pipeline component and shall be free from such defects as bare patches or lack of adhesion.
A spiralled appearance is permissible provided that the zinc-rich paint coating masses comply with the requirements of 5.4.
The manufacturer shall define those coating irregularities which are considered not detrimental to the performance of the coating system.
Damaged areas of zinc-rich paint coating caused by handling are acceptable, provided that the area of damage is less than 5 cm2 per square metre and that the minor dimension of the damaged area does not exceed 5 mm. Greater areas of damage shall be repaired in accordance with 5.5.
The mean mass of zinc-rich paint coating measured in accordance with 7.1 shall be as follows:
一not less than 235 g/m2 with a local minimum of 210 g/m2;
一in low corrosive areas, by agreement between the purchaser and the supplier, 150 g/m2 with a local minimum of 130 g/m2.
NOTE The masses of zinc-rich paint coating are equivalent to 200 g/m2 with a local minimum of 180 g/m2 of metallic zinc coating (first case) and 130 g/m2 with a local minimum of 110 g/m2 of that (second case).
Where there are very corrosive soils the manufacturer and the purchaser may decide to use an additional coating mass of zinc-rich paint. For the selection of coatings in relation to the characteristics of soils Annex B can be consulted.
The manufacturer shall visually inspect each pipeline component for quality and uniformity of coating and shall carry out regular measurements of zinc-rich paint coating masses in accordance with the method described in 7.1.
The factory quality control tests ensure conformity to the standard. Where informative field verification is required, one of the methods described in Annex A shall be agreed upon between the manufacturer and the purchaser.ISO 8179-2 pdf download.
