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2PE anti-corrosion production line: 2PE anti-corrosion (second layer of polyethylene pipe layer PE anticorrosive structure, the first layer adhesive (AD), the second layer of polyethylene (PE), two kinds of materials as a whole, the thickness of each layer and three layer PE same. It can be seen from the difference is: the 3PE anticorrosion more a layer of epoxy powder, and epoxy powder resistant corrosion resistance, good mechanical performance, strong resistance to cathodic disbonding, although it has a surface treatment strictly, poor weather resistance, bibulous rate is high, etc., but it is useful to buried seabed pipeline, coating layer thickness is only 0.3 to 0.5 mm, service life of up to 40 ~ 50 years.