The domestic pipeline anti-corrosion coating starts the application of petroleum asphalt. Double-sided submerged arc welding spiral steel pipe was built in 1958. China's long-distance oil gas pipeline Karamay to Dushanzi oil pipeline uses petroleum asphalt horseshoe grease for external corrosion Layer, until the Northeast oil pipeline constructed in the 1970s, still used petroleum asphalt as the external anti-corrosion coating. During this period, petroleum asphalt anti-corrosion layer was the main domestic pipeline anti-corrosion coating technology, which developed a single petroleum asphalt structure to a multi-layer structure compounded with glass cloth.
Starting the 1970s, drawing on foreign pipeline anti-corrosion coating technology, China has carried out research development application of pipeline anti-corrosion materials such as epoxy coal asphalt coating, polyethylene adhesive tape, coal tar enamel, etc., breaking the petroleum asphalt Antiseptic dominates the world
In the early 1980s, China began to develop apply the technology of extruded polyethylene anti-corrosion layer (2PE) the technology of polyurethane foam polyethylene outer protection anti-corrosion insulation layer; later developed introduced sintered epoxy powder a new generation of coal tar enamel other pipeline anti-corrosion materials technologies.
In the mid-1990s, with the need for large-scale oil gas long-distance pipeline construction, the domestic introduction of the internationally advanced three-layer structure polyethylene (3PE) anti-corrosion coating technology has become the main external anti-corrosion coating for oil gas pipelines. One of the technologies; in the late 1990s, China began to introduce double-layer sintered epoxy powder coating technology three-layer structure polypropylene (3PP) anti-corrosion coating technology, which has been applied on a small scale, but it is receiving increasing attention.
In order to further meet the needs of pipeline anti-corrosion coating applications, more more new materials new technologies are constantly being developed applied, such as polyurethane vinegar coatings with 100% solids content, poly-vessel elastomers, solvent-free liquid epoxy coatings. Etc., will further enrich the choice of anti-corrosion coating technology for oil gas pipelines.
The pipeline anti-corrosion coating systems listed in the US NACE standard RP0169-2002 are: coal tar (Coal Tar), paraffin (Wax), prefabricated film (cold wound tape) (PrefabricatedFilms), sintered epoxy coating (Fusion-bonded EpoxyCoatings), polyolefin coatings (Polyolefin Coatings), etc. In addition to paraffin, these pipeline anti-corrosion coating technologies have been developed applied in China, the localization of anti-corrosion materials has been achieved.
At present, a series of industry technical standards have been formulated for the external anti-corrosion coating technology of oil gas pipelines. The anti-corrosion coating technologies involved include: petroleum asphalt, epoxy coal tar, coal tar enamel, polyethylene adhesive tape, fusion ring Oxygen powder (FBE), polyethylene anti-corrosion layer (2PE, 3PE), polyurethane anti-corrosion coating, etc .; CNPC enterprise standard has been developed with double-layer sintered epoxy powder coating technology. The formulation implementation of these standards have promoted the application of corresponding anti-corrosion coating technology, but it is necessary to continuously study improve the actual application effects existing problems to further ensure the long-term quality service life of anti-corrosion steel pipes.