At present, there are two standards for 3PE anti-corrosion steel pipes, namely GB/T 23257-2009 and GB/T 23257-2017. GB/T 23257-2017 is a new standard and was implemented in December 2017. The two standards differ mainly in the following aspects:
3PE anti-corrosion steel pipe
1. The design temperature of the anti-corrosion layer is different. The old standard (GB/T 23257-2009) is 50 degrees at room temperature, 70 degrees at high temperature, 60 degrees at room temperature, and 80 degrees at high temperature.
2.3 The thickness of the anti-corrosion layer of the welded seam of PE anti-corrosion steel pipe shall not be less than 70% of the old standard and 80% of the new standard.
3. The thickness of the old standard epoxy powder is greater than or equal to 120 microns, the diameter of the new standard steel pipe is less than 500 and greater than or equal to 120 microns, and the diameter of the steel pipe is greater than or equal to 500 and greater than or equal to 150 microns.
4. The old and new standards for the total thickness of the anti-corrosion layer less than 1200 are the same. The old standard for diameters greater than 1200 is 3.0 mm with a reinforced grade of 3.7 mm, and the new standard is 3.3 mm with a reinforced grade of 4.2 mm.
5. Other aspects are better than the old standard.