Anticorrosion test of precision bright seamless steel pipe
Anti corrosion inspection of precision bright seamless steel pipe:
1. Coating inspection and acceptance:
① During and after surface coating construction, the coated workpiece shall be protected to prevent dust and other debris.
② After coating treatment inspection, the coating color should be consistent, bright color, no wrinkle skin, blister, sagging, missing coating and other defects.
③ The thickness of coating film is measured by contact type paint film thickness meter. Generally, the thickness of three points is measured by paint film thickness gauge, and the average value is taken.
2. Quality inspection
① The quality inspection shall be carried out by sampling according to the design regulations.
② Check one by one with visual inspection. The surface of the covering layer should be uniform and flat, without bubbles, wrinkles, bumps and uneven blank holder defects
③ The thickness of paint film is measured by magnetic thickness gauge, and one point is measured every 1.5 meters on both ends and middle circumference of single section precision bright tube. The paint film thickness shall meet two 85%: that is, 85% of the measuring point thickness meets the design requirements, and the minimum value of the measuring point that cannot reach the thickness shall not be less than 85% of the design thickness;
④ Check the pinhole with a pinhole tester. If any pinhole is found, polish it with sandpaper grinder;
⑤ If the thickness of paint film is insufficient or there are pinholes, recheck it after repair and curing. If it is unqualified, it should be repaired again until it is qualified;
⑥ For adhesion inspection, use a hard cutting tool to mark a 60 angle incision on the coating for spot check. The coating should be cut through to the substrate directly. The scratch part should be pasted with adhesive tape. After tearing off the tape, the scratch should be observed. The coating should not be peeled off. Inspection can also be carried out on the sample plate painted under the same conditions.
