1, the appearance: the pipeline for a full-line visual inspection, in the prefabricated plant should be root-by-root visual inspection, filling, injury should be checked one by one, the surface of the anti-corrosion layer should be flat, evenly connected, no bubbles, creases and breakage.
2, thickness: according to the "pipe anti-corrosion layer thickness non-destructive measurement method (magnetic method)" SY0066 to measure. One for every 20 spot checks, one random measurement, each in the direction of the circumference about the uniform distribution of four points; When the thickness is not qualified, should double the spot check, still unqualified, it is judged to be unqualified.
3, peeling strength: with a knife ring to cut open 10mm wide, the length of more than 100mm polypropylene anti-corrosion cold tangled, until the tube body. Then use a spring scale and the pipe wall into a 90-degree angle to pull apart, the pull speed should not be greater than 300mm/min. The peeling strength shall comply with the provisions of Table 1.3.2 of this standard. This test should be performed after wrapping the tape 4h. Three sections should be tested per kilometer of anti-corrosion pipeline, and the number of spot checks at the filling and injury fillings shall be 1% of the filling and injury.
4, spark detection leakage: in the prefabricated plant should be root by root inspection, in the field of the pipeline to carry out a full-line inspection, filling, repair injuries should be checked one by one. The leak detector does not move faster than 0.3m/s, qualified without sparks.
about polypropylene anti-corrosion cold tangled layer anti-corrosion layer quality standards and inspection methods in the above in a detailed introduction, in order to extend the anti-corrosion time of cold tangled belt and steel pipe service life, it is necessary to strictly follow the above inspection methods for anti-corrosion layer testing, if found to be unqualified should be repaired. After the repair is completed, the test will be carried out again in accordance with the above standards until it is qualified.