Comparison of polyethylene anticorrosive tape and petroleum asphalt glass cloth

　　Petroleum bitumen glass cloth anticorrosive pipeline prefabrication process and production situation

　　 Petroleum bitumen glass cloth anticorrosive layer has always been the main material for external anticorrosion of buried steel pipelines in oil fields. Daqing Oilfield has successively investigated and tested 500km asphalt anticorrosive pipelines. The investigation found that pipeline anti-corrosion coatings built after 1985 are generally inferior to pipelines built in the 1960s and 1970s. The reason is related to the raw materials and construction. Petroleum asphalt (usually 10# construction asphalt) has complex composition, unstable quality, low softening point, low temperature and cold brittleness, high temperature flow, and poor aging resistance; the outer protective layer polyethylene industrial film has poor adhesion to asphalt, and mechanical Low strength, easy to be damaged or man-made damage, resulting in the reduction of water resistance and penetration resistance of reed rhizomes of the entire anti-corrosion layer, and shortened service life. In addition, the asphalt coating process is complicated, the construction temperature is high, the environmental pollution is serious, and the labor intensity of the workers is high. The coating quality is not easy to control. In recent years, with the continuous improvement of the quality and performance of polyethylene tape products, the continuous development and improvement of construction equipment and technology, its comprehensive performance is better than petroleum asphalt. Daqing Oilfield has prepared to use polyethylene tape or a composite structure of tape and coating to replace asphalt glass cloth for anticorrosion on pipelines with large investment and long service life, such as oil pipelines.

　　Polyethylene tape anticorrosive pipeline prefabrication process and production situation

　　Polyethylene tape has excellent construction performance and a wide range of suitable construction temperature. The construction is convenient and the methods are various. It can be prefabricated in the factory or on-site; it can be constructed by winding machinery or manually. The prefabrication process is simple: (1) moving and removing rust: (2) applying primer; (3) wrapping tape. No environmental pollution, fast construction speed, and high efficiency. For example, the small pipe operation line of Daqing Oil Construction No. 2 Company has a batch of 3 people and can produce 3km of Ф76 pipeline every day. The polyethylene tape pre-manufacturing line and equipment are not complicated and occupy a small area. The asphalt anticorrosion line or the foam jacket line can be slightly modified and a tape winding device can be added.