According to the oil and gas industry standard SY/T 0315-97, the adhesion performance of the anti-corrosion pipeline coating is determined by the following method.
(1) Equipment required for the test
① Beaker.
② Thermometer.
③Universal knife.
(2) Test piece
The size of the laboratory coating test piece is about 100mmx100mmX6mm, and the size of the pipe section test piece is 100mmX100mmX pipe wall thickness. Each group of test pieces is 3 pieces.
(3) Test procedure
①Put the sample into a beaker, add enough water to fully submerge the sample, heat to 75°C±3°C for at least 48h or to 95°C±3°C for at least 24h, then take out the test piece.
②When the test piece is still warm, immediately use a knife to draw a rectangle of about 30mmX15mm on the coating, the knife mark penetrates the coating to reach the base plate, and then cool naturally in the air to 20°C ± 3°C. Insert the tip of the knife under the normal layer from any corner of the rectangle within 1 hour after taking out the sample, pry and peel off the coating with a force in the horizontal direction, and push the tip of the knife continuously until all the coating in the rectangle is pried off or the coating shows Obvious prying performance.
③Assess the adhesion level of the rectangular inner coating according to the following grading standards:
Class 1 - Coating visibly cannot be peeled off by prying.
Class 2 - Less than or equal to 50% of the coating has been pried off.
Level 3—more than 50% of the coating is pried off, but the coating shows obvious prying resistance.
The grade 4 layer is easily peeled off into strips or large fragments.
Class 5—The coating has been peeled off in one piece.
(4) Result representation
The test result of the lowest level among the three test pieces represents the adhesion level of this group of test pieces.
