GPS communication technology and its application in the detection of coating defects of buried pipelines;

This paper analyzes the performance of pipe coating, and based on the equations given in relative design codes and engineering manuals, the different program of sacrificial anode sets can be selected depending on different coatings and pipe diameters.

According to the medium through soil in the pipeline,the type and quantity of pipelines,three PE external anticorrosion coating plans plus cathodic protection are chosen in the protection design,and construction requirements are prosposed.

Based on analyses of the current international anticorrosion inspection techniques, we proposed a novel inspection method for the status of the underground metal pipelines anticorrosion coating—the current gradient method.

Based on an introduction to the detection technology of external anticorrosive coating of buried pipeline in service, the narration is given to the working principle, measuring techniques of PCM system, and basic methods of detecting the rank of anticorrosion coating according to the relevant technological regulation and standards.

The DCVG & CIPS measurement technique is a main method applied in integrity testing of external anticorrosive coating of gas transmission pipeline.

In pipeline connection,conventional welding technique affected anticorrosion performance due to the destruction of anticorrosive coating on pipeline inner wall,whereas the use of HP(high pressure)snap joints can ensure the integrity of anticorrosive coating thoroughly and solved the problem of internal end-to-end joint coating for pipeline weld.

In this article, the technique research and development process of application of poly ethylene to anticorrosion layer on piping for conveying oil was introduced, and the optimum composition and technical route to change the properties of poly ethylene were presented as well.

Fast connection stud of high pressure piping is used to replace for welding in connection of piping so as to keep the integrity of the anticorrosion layer.

Presents a method of current attenuation,which is used for underground pipeline inspection,and discusses how put it into application for 3PP pipeline coating in semi-desert with the characteristics of high soil resistance.

The application status quo of pipeline coatings in different stages and development tendency of pipeline coatings at home and abroad are described.

Three pipeline coating detection technologies, multiple-frequency current method, ground potential-electrical field method,and pipe-to-soil potential method,are introduced.