The anti-corrosion technology of seamless steel pipes is crucial to protect the pipes from corrosion and extend their service life, especially when they are exposed to corrosive environments. There are several common anti-corrosion technologies used for seamless steel pipes.
Coating Systems:
Internal Coating: For pipes that carry corrosive fluids, applying internal coatings can prevent corrosion and protect the material being transported.
External Coating: External coatings protect the outer surface of the pipe from environmental corrosion. Common external coatings include:
Fusion-Bonded Epoxy (FBE): Applied as a dry powder to the heated pipe surface, forming a protective layer.
3-Layer Polyethylene (3LPE) or Polypropylene (3LPP): Consists of a fusion-bonded epoxy layer, an adhesive layer, and a polyethylene or polypropylene layer.
Cathodic Protection:
Galvanic Cathodic Protection: Involves attaching sacrificial anodes (usually made of zinc or magnesium) to the steel pipe. These anodes corrode instead of the steel, providing protection.
Impressed Current Cathodic Protection: Uses an external power source to apply an electric current to the steel, preventing corrosion.
Corrosion Inhibitors:
Chemical Inhibitors: Corrosion inhibitors can be added to the fluid being transported in the pipe to reduce the corrosive effects on the steel.
Wrapping Tapes:
Bitumen-Based Tapes: Applied as a tape over the external surface of the pipe, providing a protective layer against corrosion.
Thermal Spraying:
Metallic Coatings: Application of a metallic coating (such as zinc or aluminum) on the surface of the pipe using thermal spraying methods.
Cement Mortar Lining:
Internal lining of pipes with a layer of cement mortar to protect against corrosion in water and wastewater applications.
When selecting an anti-corrosion technology for seamless steel pipes, factors such as the environment, type of fluid being transported, temperature, and expected service life should be considered. It's common to use a combination of these techniques to provide comprehensive protection against corrosion. Additionally, adherence to industry standards and proper quality control during the application of anti-corrosion measures is crucial to ensure their effectiveness.