Surface treatment

1. Sandblasting: Remove rust and oxides from the surface by spraying sand at high speed.
2. Pickling: Use acid to remove rust and oxides from the surface.

Coating anti-corrosion

1. Epoxy coating: excellent adhesion and corrosion resistance.
2. Polyurethane coating: good wear resistance and corrosion resistance.
3. Polyethylene coating: thick anti-corrosion protective layer.

Hot-dip galvanizing

1. Pretreatment: clean the oil, scale and rust on the surface of the steel pipe.
2. Hot-dip galvanizing: immerse in zinc liquid to form a zinc coating.
3. Cooling treatment: take out and cool and check the quality of the zinc layer.

Cathodic protection

1. Impressed current protection: DC current is applied to make the steel pipe a cathode.
2. Sacrificial anode protection: A metal with a lower potential than the steel pipe (such as magnesium or zinc) is buried as an anode to corrode first.

Other anti-corrosion methods

1. Fusion bonded epoxy powder coating (FBE): Electrostatic spraying of epoxy powder forms a dense coating.
2.3PE anti-corrosion coating: It consists of epoxy powder layer, adhesive layer and polyethylene layer, suitable for buried and underwater pipelines.