The anti-corrosion process of 3PE anti-corrosion steel pipe refers to the treatment of steel pipes with anti-corrosion technology that can effectively prevent or slow down the corrosion caused by chemical or electrochemical reactions during transportation and use.
The 3PE anti-corrosion steel pipe is a commonly used three-layer polyolefin coating (MAPEC) anti-corrosion steel pipe in China. It comprises three layers: the first layer is epoxy powder (FBE, greater than 100um), the second layer is an adhesive (AD) with a thickness of 170250μm, and the third layer is polyethylene (PE) with a thickness of 2.53.7mm. Other anti-corrosion methods include IPN8710, FBE epoxy powder, and epoxy coal tar pitch.
The painting requirements mainly encompass the following three aspects:
Excellent Corrosion Resistance: The coating formed by the anti-corrosion paint should remain stable when exposed to various corrosive media such as acids, alkalis, salts, industrial sewage, and chemical gases. It should not be dissolved, swollen, or decomposed by these media, nor should it react with them to produce new harmful substances.
Good Impermeability: The coating should effectively prevent penetration and rectify corrosion on the pipe surface when in contact with highly permeable liquid or gas media.
Excellent Adhesion and Flexibility: The coating should not detach due to pipe vibrations or slight deformations. It should possess a certain degree of mechanical strength.
Epoxy anti-corrosion coatings are widely used for the corrosion protection of both inner and outer walls of pipelines due to their strong adhesion, resistance to acids and alkalis, and low shrinkage rate. However, they have drawbacks such as poor weather resistance, which can lead to easy chipping, especially when the curing process is not optimal. In such cases, the coating's water resistance decreases, making it prone to whitening and brittleness.
