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If anti-corrosion steel pipes are classified according to their types, they can be mainly divided into several forms: anti-corrosion spiral steel pipes, anti-corrosion straight seam steel pipes, and anti-corrosion seamless steel pipes. The common form of anti-corrosion steel pipes on the market now is 3pe anti-corrosion. 
The SY/T0413-2002 standard has been implemented domestically since August 1, 2002. The standard mainly specifies polyethylene and high-density polyethylene, with a Vicat softening point set at not less than 110 ℃; The thickness of the external anti-corrosion layer is determined according to the German standard DIN30670-1991, which mainly uses low and medium density polyethylene. Improved the impact resistance of the 3PE anti-corrosion coating. SY/T0413-2002 significantly improves the peel strength and impact resistance indicators of the 3PE anti-corrosion layer, and specifies that based on the carbon black content of some special materials, the mechanical strength and weather resistance of the 3PE anti-corrosion layer have been improved, and the sampling frequency of the joint peeling strength (i.e. the peeling strength of the heat shrink sleeve and heat shrink tape to the primer steel) has been increased. 
The anti-corrosion spiral steel pipe 3PE structure anti-corrosion coating combines the advantages of high-density polyethylene coating and fusion bonded epoxy powder. The epoxy powder of this system is firmly bonded to the surface of the steel pipe, utilizing high-density polyethylene to resist mechanical damage. The special adhesive layer between the two layers forms a composite structure of molecular bonds, thereby achieving a good combination of anti-corrosion and mechanical properties.