The performance of the pipeline in the corrosive environment changes

Petroleum chemical industry, shipbuilding, coating steel pipe media such as offshore oil platforms, there are many corrosive, in fact, the dangers of metal corrosion is very common, but also is very serious, the corrosion cause direct or indirect losses. For example, between the metal corrosion and stress corrosion and fatigue corrosion tend to major catastrophic accident, and the metal corrosion can cause a lot of metal consumption, waste lots of resources. Mainly has the following cause corrosion medium.

1. Chloride and chloride corrosion of carbon steel is basically uniform corrosion, and accompanied by hydrogen embrittlement, corrosion is pitting corrosion of stainless steel intergranular corrosion or. Prevention measures can choose appropriate materials, such as the use of carbon steel pipeand stainless steel composite pipe.

2. As many as 250 sulfide sulfur in crude oil, on the metal corrosion of hydrogen sulfide (H2S), mercaptan (R - SH), sulfide (R - S - R), etc. The high H2S content in the liquefied petroleum gas in our country, causing cracks in container, some production of the 87 days that happen through cracks and later by the magnetic particle inspection, inner surface circumferential weld crack, 417 ball in vitro surface crack, so the high content of H2S stress corrosion caused by deserve attention. Japan welding society and high pressure gas safety association rules: H2S content in the liquefied oil should be controlled under 100 x 10-6, but our country liquefied petroleum gas H2S content in an average of 2392 x 10-6, Japan more than 20 times higher.