Depending on the specific use of the steel pipe, some painting or coatings may be used for different applications. When it comes to hot dipped galvanized steel pipe in the pipe market, zinc is a very durable coating for the purposes of providing sacrificial protection to the underlying steel substrate but,because it is reactive to water, great care must be taken in storing it correctly so as to avoid the potential “wet storage stain.”Generally speaking, the surface of galvanised coatings is almost 100% zinc. It is the durability of the zinc that provides the outstanding anti-corrosion performance for steel, yet zinc is a relatively ‘reactive’ metal. It is the stable oxides that form on the zinc's surface that determine its durability, and these oxides are formed progressively as the zinc is exposed to the atmosphere.
Asit is well acknowledged, round steel pipe is a very important building material, widely used in the construction field. In the actual procurement, customerstend towards certain strict requirements for the quality assurance of the pipe, for even minor corrosion requires repairs and maintenance.In the pipe processing, more and moresteel pipe manufacturers will generally make a specific treatment for pipe in advance as per different requirements of customers.Coatings provide two primary functions—decoration and protection—that are of considerable economic importance. Functional coatings may be applied to change the surface properties of the substrate, such as adhesion, wetability, corrosion resistance, or wear resistance. In the steel industry, paint coating mainly protectsteel pipefrom corrosion, as well as maintain a pretty appearance of pipe.Paint coatings serve as a barrier to prevent the transfer of electrochemical charge from the corrosive solution to the metal underneath. However, the additional cost will somewhat bring about an increase in the steel pipe price.
Today, much progress has been made in the practice of using coating technology to offer corrosion protection to offshore structures, inner-hull tanks in fuel tankers, ship hull, underwater pipes, etc. New methods have been developed to repair and protect various welded steel pipe in coastal and offshore waters, such as the all-polymer encapsulation technique to repair and protect structures in the splash zone. Long-term structural or mechanical requirements for a particular application can be assured through corrosion protection, through either coatings or a combination of cathodic protection and coatings.