What Does Primed Steel Mean?
Primed steel is steel prepared by the application of a primer or undercoat before painting. Priming enhances the coating's adhesion to the steel surface. It provides extra protection for the steel and coating durability. Primed steel helps prevent corrosion and oxidation, and improves the life of the material.
Primed steel is used in many industries, including maritime, highways and bridges, infrastructure development and tank manufacturing.
Corrosionpedia Explains Primed Steel
Primed steel refers to steel that is enhanced by the process of painting the steel with a primer consisting of resin, additives and solvents. Primer containing polyethylene (plastic) provides better durability and corrosion protection. When priming a steel, it is necessary to control porosity, tackiness and hygroscopy of the primer to achieve good coating adhesion.
A bare steel part oxidizes to form rust. Consequently, the bare steel surface has poor paint adhesion and as a result, paint will come off in large flakes. In this scenario primed steel provides good adhesion to the paint and helps the coating stick on the metal surface for a longer time. Priming also helps to minimize poor conditions on the metal's surface.
There is a difference between galvanized steel and primed steel. Galvanized steel has been treated with a zinc coating whereas primed steel has been primed with a metal primer before painting. Galvanized steel is rustproof without additional coating while primed steel requires additional coatings to protect against corrosion.
In underground and offshore pipelines, polyethylene tape is used to cover the primed steel pipes' surface so it is protected from chemical electrolytic corrosion.