The general opinions of the owner, supervision, design unit and construction unit of the large-scale pipeline petrochemical project, and the general reasons for strengthening the bubble of the cold-wrapped anti-corrosion tape during the winding process are as follows:

1. The temperature difference between the pipe body and the adhesive tape.

2. The temperature change of the atmosphere, the larger the pipe diameter, the greater the influence of the anti-corrosion layer.

3. In addition to incomplete or windy sand, there are foreign objects on the surface of the pipeline.

4. Since the steel pipe absorbs heat, and the black color of the anti-corrosion tape is more endothermic, the pipe body is prohibited from exposure after anti-corrosion, and should be stored according to requirements. Because the sealing property of the tape is relatively good, the water vapor can not penetrate the anti-corrosion layer for a long period of time, resulting in bubbles.

5. In the SY/T 0414-2007 standard:

1) It is clearly stated that when the weather is hot or sunny, there are often bubbles generated when the adhesive tape is wound. Since the adhesive tape itself has a certain elasticity and self-repairing ability, these bubbles may disappear on their own, so this kind of bubble The situation is not necessarily a quality issue. If permanent bubbles are created, like wrinkles, repair should be removed.

2) The generation of bubbles is, in the final analysis, the thermal expansion and contraction of the polyethylene-based film, which is not a construction quality problem. The general solution is to take appropriate measures to prevent direct sunlight from illuminating the surface of the steel pipe after the external corrosion protection of the steel pipe is completed, such as covering the steel pipe with straw or mesh cloth. This can avoid tape aging and reduce bubble generation.

3) Steel pipes that have generated bubbles are in a low temperature condition, such as rainy days and buried, the bubbles will be eliminated by themselves, and it is not suitable to locate quality problems.