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Due to the long distances over which natural gas pipelines are transported, and the complex environments they pass through along the way, various factors can affect pipeline transportation and pose threats to its safety, thereby creating risks to the safety of lives and property. Managing the integrity of gas pipelines involves comprehensive and systematic oversight of such pipelines, identifying potential safety hazards, and preventing safety incidents from occurring. During use, pipelines suffer from corrosion damage to varying degrees, and maintenance personnel need to conduct corrosion inspections and repairs on the inner and outer walls of the pipelines to ensure their integrity. This article discusses the integrity management of long-distance natural gas pipelines and pipeline corrosion monitoring techniques. After being extracted and processed, natural gas is transported via pipeline from the mining sites to purification plants. Following purification, it is sent through long-distance natural gas pipelines to utility companies in cities, where it is used for industrial purposes or in residential homes. From production to use, natural gas is transported through enclosed pipelines. Long-distance pipelines are the conduits that connect gas purification plants to cities; due to the long distances involved and the various terrains they must pass through, the inspection and maintenance of these pipelines pose a challenge. If a leak occurs in such pipelines, it can cause serious damage to the environment as well as to people’s lives and property. Carrying out integrity management of pipelines and corrosion testing can help identify potential safety hazards and reduce the occurrence of accidents; it is an important measure to ensure the proper operation of pipelines. 1 Integrity management of long-distance pipelines: Pipeline integrity refers to the condition in which the pipeline is in a safe and reliable operating state, allowing operators to take measures to prevent accidents from occurring. Every aspect of pipeline design, including pressure, construction, and maintenance, affects the integrity of the pipelines. Pipeline integrity management refers to the process by which regulatory authorities identify risk factors associated with pipelines in use, and develop corresponding control measures to keep those factors that could lead to accidents within acceptable limits. Integrity management of pipelines requires staff to conduct regular inspections of the pipelines, carry out risk assessments, and take appropriate measures to reduce the likelihood of accidents. As the pipes are in use for an extended period of time, they may suffer from aging, corrosion, and mechanical damage during operation; therefore, it is necessary for staff to inspect the pipes to ensure their integrity. The integrity management of pipelines mainly includes the following aspects. 1.1 A sound and well-established integrity management system for long-distance pipelines ensures that the measures related to pipeline integrity are clearly defined. Strict management regulations are formulated, and a mature and comprehensive management framework for such pipelines is put in place. This framework includes a mechanism for ongoing identification of safety hazards, thereby keeping the risk levels of the pipelines at acceptable levels. For pipelines with safety hazards, appropriate countermeasures are taken to address the safety risks associated with them. 1.2 Analysis of safety hazards: An analysis is conducted on long-distance pipeline systems to identify the factors that affect their integrity, and necessary corrective actions are taken for any existing hazards in order to ensure the integrity of the pipelines. In areas prone to natural disasters such as landslides, these disasters can cause collisions or compression against pipelines, leading to ruptures and perforations in them, which in turn affects the normal delivery of natural gas through those pipelines. Therefore, in regions with harsh geological conditions and frequent natural disasters, it is necessary to protect the pipelines and establish emergency measures to address the safety risks posed by such disasters, ensuring the safe operation of the pipelines. Construction carried out by third parties can also cause damage to the pipelines; since the construction teams are not aware of the presence of these gas pipelines, they end up damaging them during construction, resulting in leaks. If not dealt with promptly, it can cause severe safety accidents, resulting in injuries or even death. 1.3 To establish a database for the integrity of long-distance natural gas pipelines, modern management methods are employed to collect and monitor data related to the integrity of these pipelines, which is then entered into computer databases. Through data management systems, statistical analyses of the pipelines’ operational parameters are carried out to generate reports that serve as a basis for managing pipeline integrity. Information on the corrosiveness of the gas pipelines is combined with production databases to conduct studies on integrity, and modern data management techniques are used to improve the level of integrity management. 1.4 Strengthening the integrity management of long-distance pipelines: Since long-distance natural gas pipelines have a long service life after being constructed, it is necessary to enhance the monitoring of construction quality. During the design phase, it is necessary to arrange the locations of gas transmission stations and pipelines in a logical manner to ensure construction quality, strengthen the management of the pipeline system, and reduce the likelihood of accidents. Establish safety management measures for long-distance pipelines, provide enhanced training for employees to improve their operational skills in pipeline maintenance, set up a pipeline management system to monitor the operational status of the pipelines in real time, assess safety risks, develop countermeasures, reduce the likelihood of safety incidents, and ensure the integrity of the long-distance pipeline system. 2 Pipeline corrosion monitoring technology: As of current technology, using steel pipelines for transporting natural gas is considered the safest and most reliable method. However, over time, these pipelines can develop defects such as corrosion and perforations, which pose safety risks. Therefore, corrosion monitoring of pipelines is an important means to ensure transportation safety. Pipeline corrosion can be divided into internal and external corrosion. Internal pipeline corrosion refers to the damage caused to the pipeline by corrosive impurities in the medium flowing through it, leading to phenomena such as pitting and bubbling that damage the interior of the pipeline. External corrosion of pipelines refers mainly to the peeling off of the anti-corrosion coating on the outside of the pipeline, which allows the pipeline to come into contact with the soil; acids and alkalis in the soil then cause corrosion of the pipeline. 2.1 Internal pipeline corrosion detection technology: This technology is a non-destructive testing device for cleaning pigs, used to collect and analyze information within the pipeline. By scanning the pipe section by section, it detects defects caused by internal corrosion. The main techniques for detecting corrosion inside pipelines are as follows: ； (1) Magnetic flux leakage method intelligent pig: The magnetic flux leakage method intelligent pig is a testing device that has been in use for a long time and whose technology is relatively mature; it can detect changes in the thickness of the pipe wall as well as any dents in the wall caused by corrosion inside or outside the pipeline ； (2) Eddy current testing technology: This technology makes use of the principle of electromagnetic induction; by measuring the changes in the eddy currents generated within the pipe wall, it is possible to assess the performance of the pipe wall as well as the presence of any defects caused by corrosion ； (3) Ultrasonic crack detector: The ultrasonic crack detector uses ultrasonic waves to detect and locate cracks, pores, and other defects in the pipe wall caused by corrosion, thereby enabling risk assessment and diagnosis. 2.2 Techniques for detecting external corrosion of pipelines There are many technical methods for detecting external corrosion of pipelines both domestically and internationally. Based on the type of signal source, these methods can be divided into direct current and alternating current types. Currently, the detection of the corrosion status of anti-corrosion coatings is mainly carried out by taking measurements on the ground above the pipeline or by testing the performance of those anti-corrosion coatings. Two commonly used methods are described below. (1) Current method in multi-frequency tubes: The current method in multi-frequency tubes is a technique based on the current measurement within the tubes, used to detect leaks in the protective layer of buried pipes. It enables determination of the depth at which the pipes are buried as well as the overall integrity of the anti-corrosion layer, thus facilitating maintenance and repair efforts by the parties responsible for using these pipes ； (2) Pearson testing method: The Pearson testing method involves applying an alternating current signal between the pipeline and the ground; by measuring the gradient of the alternating voltage, it is possible to detect damage to the pipeline’s anti-corrosion coating and locate the area where the coating is damaged. 3 Conclusion In the management of long-distance pipeline integrity, it is necessary to assess the corrosion condition of the inner and outer walls of the pipelines, estimate risks, and develop maintenance plans to ensure the safety of natural gas transportation over long distances.