Corrosion anticorrosion coatings

Corrosion. Anticorrosion measures have become standard ia pipeline desiga, coastmctioa, and maintenance ia the oil and gas iadustries the principal measures are appHcation of corrosion-preventive coatings and cathodic protection for exterior protection and chemical additives for iaterior protectioa. Pipe for pipelines may be bought with a variety of coatiags, such as tar, fiber glass, felt and heavy paper, epoxy, polyethylene, etc, either pre-apphed or coated and wrapped on the job with special machines as the pipe is lowered iato the treach. An electric detector is used to determine if a coatiag gap (hoHday) exists bare spots are coated before the pipe is laid (see Corrosion and corrosion control). 

Sulfonic acid salts have found widespread use in the area of corrosion inhibition. Lubrizol Corporation produces a wide variety of sulfonic acids, particularly in the form of magnesium salts, for use in lubricant formulations, anticorrosion coatings, greases, and resins (146,147). Petroleum sulfonates are used in epoxy resin elastomers to improve anticorrosion properties of coatings and sealants (qv) (148,149). 

Anticoccidial activity, of polyether antibiotics, 20 135-136 Anticoccidials, 20 135—136 Anticorrosion agents, molybdenum compounds in, 17 39 Anticorrosion coatings, organic titanium compounds in, 25 134 Anti-corrosion metallic coatings, 1 713-714 Anticorrosion pigments, 19 411 Antidegradants... 

Exterior surface corrosion or rusting of pipes occurs by the formation of iron oxides. Painting to an appropriate specification will significantly extend the period to the onset of corrosion, but the durability of the paint finish is largely dependent on the quality of the surface preparation as well as the thickness of the coated film. Improperly installed insulation can provide ideal conditions for corrosion and should be weatherproofed or otherwise protected from moisture and spills to avoid contact of the wet material on equipment surfaces. Application of an impervious coating such as bitumen to the exterior of the pipes is beneficial in some circumstances. Hypalon and neoprene rubber-based anticorrosive coatings admixed with chlorinated rubber are finding use in many installations. 

The purpose of cleaning steel is to remove dirt and leave the article in a state in which it can be dehvered for use without further finishing. The surface must therefore be covered with a tenacious corrosion-resistant coating as it emerges from the cleaning bath. Many emulsion cleaners remove lubricants and other unwanted dirt whUe depositing an anticorrosive coating on the metal. The primary test for efficacy in this situation is a corrosive test of the cleaned article. 

Figovsky, O., Karchevsky, V., and Beilin, D. Crack-Resistant and Anticorrosive Coatings Based on Vulcanized Water Dispersion of Chlorine-Sulpho-Polyethylene, Journal Anti-Corrosion Methods and Materials 50, no. 2 (2003). 

By performing weight loss tests, technical personnel can estimate the corrosiveness of an environment over a period of time. If the corrosion rate is determined to be high, preventive measures can be taken to prolong the remaining life of the equipment. The preventive measures can include the addition of a corrosion inhibitor, a change in the process, an application of anticorrosion coatings, or the addition of a CP system. 

However, a general disadvantage of the phosphate pigments used in the anticorrosive coatings, is a low efficiency of the under-film corrosion process evolution on the initial stages, which is connected with their low water solubility, and, obtained accordingly to the described above meth-... 

Anticorrosive coatings are generally classified according to the mechanisms by which they protect a metal against corrosion. The three basic protective mechanisms of anticorrosive coatings are as follows ... 

The standard methods also include those used mainly, but not exclnsively, to test anticorrosion coatings in corrosive atmospheres, for example, in those containing SO2 and Cl". 

Uses Binder tor corrosion protection coatings, fast drying anticorrosive primers... 

Uses Binder, corrosion inhibitor for heat-resist, anticorrosion coatings for industrial equip., chimneys, car exhausts, ovens, barbecues Features Heat resist, to 350 C with temp.-stable pigments, to 650 C with metallic pigments... 

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