When referred to anti-corrosive protection,people naturally think of external anti-corrosion coating,such as three-layer polyethylene system (3LPE) and three-layer polypropylene (3LPP),but the internal anti-corrosive coating of the pipeline is as important as the external coating for protection of the pipeline.
The most widely used internal anti-corrosion options as follows:
1.Use anti-corrosion steel and corrosion inhibitor
Adopt stainless steel tube,steel-plastic composite hose and other corrosion resistant materials or carbon steel plus corrosion inhibitor technology to control internal corrosion.
Corrosion inhibitor is a kind of chemical substance that can prevent or slow down corrosion.Adding chemical preservatives such as corrosion inhibitors is the main anti-corrosion technology in submarine pipeline.
Epoxy powder internal coating for steel pipes
2. Internal anti-corrosive coating technology
Internal anti-corrosive coating is a kind of physical anti-corrosive coating,which is a thin film coating applied on the inside of the pipe body.The coating isolates the conveying medium from the inner wall of the pipe,which can not only prevent corrosion in the pipe,but also reduce the friction resistance and improve the conveying capacity.The commonly used internal anti-corrosion coating technologies are:
Epoxy powder internal coating spraying technology
Epoxy powder coating is a new type of coating which is completely solvent free,sprayed in powder form and fused into film.Good epoxy powder coating can prolong the service life of pipelines,reduce routine maintenance of pipelines,reduce operation and maintenance costs.
Epoxy powder corrosion resistance and chemical resistance, easy to construction, coating hardness,smooth appearance.
Internal spraying technology for liquid epoxy coatings
Liquid epoxy coating takes epoxy resin as the main film-forming material,and the content of epoxy resin is not less than 25%.The epoxy resin content in the coating is high,and the anti-corrosive coating has great bonding power and high mechanical strength.The curing speed is fast and the coating is compact,so that the anti-corrosive coating with excellent performance can be obtained.
Liquid epoxy powder has strong adhesion,excellent corrosion and wear resistance,electrical insulation and physical and mechanical properties.
Sealing technology of pipeline internal anti-corrosive layer
The joint of pipeline is the heat affected area of pipeline weld and the sensitive area of pipeline inner wall corrosion.At present,the commonly used internal anti-corrosion fastening technology of pipeline includes:internal coating patch technology,lining short pipe patch technology, mechanical pressing and internal patch technology,etc.
The maturity and construction quality of pipeline internal joint technology are directly related to the overall effect of internal anti-corrosive layer protection.
Haihao Group supply seamless steel pipes,welded steel pipes(ERW,SSAW,LSAW),casing and tubing in high quality,the products can coat external and internal anti-corrosive coating like 3PE,2PE,FBE,etc.If you want to know more about our pipeline products,please email us:sales@haihaogroup.com
