The anticorrosion of buried steel pipes is the key procedure to ensure and prolong their service life. In order to ensure that the anti-corrosive insulation layer is firmly combined with the pipe wall, the most important thing is the derusting of the pipeline.
Generally, the rust on the surface of the American standard steel pipe can be divided into floating rust, medium rust and heavy rust according to the delivery time, storage and transportation conditions, and the degree of climate humidity.
Floating rust: Generally, when there is a short delivery date, and there is a small amount of thin rust on the surface of the tube when it is not stored in the open air, the metal luster can be exposed by manual operations such as wire brush, sandpaper and cotton yarn.
Medium rust and heavy rust: When the factory date is long and the open storage or multiple transfers and transportation are long, the surface of the tube is oxidized and rusted, and the rust spots are heavy. In severe cases, the scale is peeled off.
Severely corroded pipelines are not suitable for water delivery systems. For medium-rust pipes and large batches, rust removal machines or mechanical sandblasting can be used for mechanical derusting, which can improve labor efficiency and reduce pollution to people and air. .
When high corrosion resistance is required or the inner and outer walls of the pipe have been corroded, the chemical derusting method can be used to effectively remove the oxides on the inner and outer surfaces of the pipe.
No matter which method is used to remove rust, the anticorrosion layer should be treated immediately after the rust is removed to avoid being oxidized and corroded by the air again.