Oil and gas pipeline corrosion and protection

In the case of oil and gas pipelines, because the media they transport often have a significant degree of corrosiveness, which can cause corrosion of the pipeline, resulting in perforation and leakage accidents, which in turn cause losses to oil and gas production.


1. Analysis of Oil Pipeline Corrosion Causes

As the pipeline is usually laid underground, there is a large degree of soil corrosion and electrochemical corrosion, which causes a decline in the pressure-bearing capacity and mechanical strength of the pipeline, resulting in oil and gas leakage, and may bring fire and other accidents, bringing economic losses to the enterprise. Because of the presence of corrosive media in the soil, which makes the formation of primary cells in the pipeline conditions, resulting in corrosion perforation, causing harm to the safety of the pipeline. The quality of the pipeline will also have a greater negative impact on the entire transport work.

Usually for metal pipelines, often with cathodic protection technology to carry out the corresponding protection, and in the pipeline construction process, if there is a lack of cathodic protection quality problems, not to achieve a better cathodic protection effect, is the main cause of serious corrosion of the pipeline, and make the service life is greatly reduced.

In petroleum media, there is a certain amount of sulfur, which is a core factor in causing corrosion in pipelines, because crude oil often contains sulfur, which causes a certain degree of sulfur precipitation compounds in the pipeline. In terms of these compounds, they will generally react with the iron in the pipeline to produce ferrous sulfate compounds, but in the case of ferrous sulfate, it contains free acid, which in turn will cause hydrolysis reactions, which will aggravate the corrosion situation based on the above.

In the natural gas transmission process, there are often transport stresses, and once this aspect shows a certain degree of fluctuation, it will cause the appearance of corrosion, and the resulting minor rupture, when the resulting small cracks after a period of time, is to show the expansion of expansion, resulting in the final large break.


2. Oil & Gas Pipeline Corrosion Protection Technology

On the whole, when the form of pipeline corrosion is divided, there are two main forms, namely internal corrosion and external corrosion. As there are differences in the situation of pipeline corrosion, the operation should be carried out with the help of targeted anti-corrosion measures.

Nowadays, the internal coating technology is very well promoted and applied. In general, internal corrosion protection technology can be divided into several types, mainly corrosion inhibitor technology, internal coating technology and composite pipe technology. Specifically in terms of corrosion inhibitor technology, the application of this technology is specifically, the proportion of corrosion inhibitor, and will be injected into the pipe, so as to achieve the purpose of corrosion mitigation.


3. Analysis of Oil and Gas Pipeline Corrosion Protection Measures

(1) Cathodic protection technical measures

In order to reduce the corrosion rate of pipelines, cathodic protection must be carried out to protect the pipeline being protected as a cathode, so as to avoid corrosion of metal pipelines. The detailed operational countermeasures are cathodic protection by sacrificial anode and cathodic protection by applied current. The cathodic protection work is carried out according to the differences of pipeline systems.


(2) Technical measures for monitoring the corrosion of oil and gas transmission pipelines

In the process of laying LPG pipelines, they are often laid in soils with different properties, so there are great differences in corrosion conditions. In general, even a single gas pipeline may come into contact with many different soils.

In the pipeline, because of its surface layer there are many physical and chemical properties, so it will cause the deepening of the corrosion of the pipeline. To face this situation, it is necessary to complete the corresponding anti-corrosion work. In this process, the chemical reaction should be given sufficient attention, and in this, electrochemical reaction is one of the key components. Specifically to electrochemical reaction to analyze, there should exist as the electrode of the metal at the same time, there should also be able to reflect the environment of the electrolyte, the third must have a conductive circuit.


(3) Enhance the corrosion resistance of LPG pipelines with the help of different types of coating technologies

In order to strengthen the corresponding anti-corrosion measures, the technician should also carry out the coating operation, so as to promote the effective strengthening of the corrosion resistance. Coating technology is widely used throughout the oil pipeline anti-corrosion work, and with the help of these special anti-corrosion materials, it is very good to promote the effective extension of the pipeline life, and will make the appearance of the pipeline and the corresponding performance of better performance.


4. Conclusion

In general, in order to deeply strengthen the overall corrosion resistance of oil and gas pipelines and pipeline stress, so the technical staff must pay sufficient attention to some points. A solid study of the causes of pipeline corrosion, and then take it as a starting point to build the corresponding protective measures. From the above, it can be seen that effective protection of pipelines can be achieved with the help of technologies such as in-line coating. The application of scientific and feasible anti-corrosion measures can largely contribute to the extension of the service life of the pipeline, and can also make the effective reduction of transportation costs.