Views: 2 Author: Site Editor Publish Time: 2025-01-20 Origin: Site
First, how many anti-corrosion steel pipes are inspected?
The number of anti-corrosion steel pipes inspected is 20 per batch.
1. Thickness inspection: Measure the thickness specified by the anti-corrosion layer grade and use an anti-corrosion layer thickness gauge for inspection. One is randomly inspected for every 20 pipes, and three sections at a certain distance are measured for each pipe. Measure the top, bottom, left, and right points on each section. If the thin point is lower than the specified thickness, it is unqualified. If two more pipes are randomly inspected, and one of them is still unqualified, all are unqualified.
2. Pinhole inspection: An electric spark leak detector must be used for inspection. The ordinary grade leak detection voltage is 2000V, the reinforced grade is 3000V, and the extra reinforced grade is 5000V. It is qualified if there is no spark. One is randomly inspected for every 20 pipes, and it is measured from one end of the steel pipe to the other end. If it is unqualified, two more pipes are randomly inspected. If one of them is still unqualified, all are unqualified.
3. Adhesion inspection: After the anti-corrosion layer is cured (usually 7 days), use a knife to cut a tongue-shaped incision and tear off the anti-corrosion layer of the incision. If it is not easy to tear off, and the damaged pipe surface is still covered by the paint film without exposing the iron, it is qualified. According to the above method, one pipe is randomly checked for every 20 pipes, and one point is applied to each pipe. If it is unqualified, then another 2 pipes are randomly checked. If one of them is still unqualified, all are unqualified. The unqualified ones should be scraped off and re-applied.
Second, introduction to the anti-corrosion standards for anti-corrosion steel pipes.
1. FBE epoxy powder anti-corrosion implements SY/T0315-2005 "Technical Specifications for Single-layer Fusion Epoxy Powder External Coating of Steel Pipes".
2. 2PE/3PE anti-corrosion implements GB/T23257-2009 "Technical Standards for Polyethylene External Coating of Buried Steel Pipes".
3. Anti-corrosion surface rust removal standard: The sandblasting rust removal on the outer surface of the steel pipe shall reach Sa2 1/2 level according to the requirements of GB/T8923-2008, and the anchor pattern depth on the surface of the steel pipe shall be 40-100μm.