All stainless steel pipe coating contains principally iron and a certain rate of chromium. At this level, such elements as chromium will not react with oxygen and moisture in the environment so
API 5l steel pipe will not be corroded. This is largely because steel pipe coating forms a protective and coherent layer. What is more, oxide film can envelop the entire surface of API steel pipe and the passive or boundary layer is very thin. To be more specific, the passive layer and steel pipe coating on stainless steels exhibits a truly remarkable property in many applications. For instance, when API 5l steel pipe is damaged or abraded, the chromium in the steel pipe coating reacts can reform the oxide layer.
Thus if we increase the chromium content in steel pipe coating beyond the minimum of ten percent, the API 5l steel pipe will have greater corrosion resistance. In terms of steel pipe coating, corrosion resistance may be further improved and a wide range of properties are offered by API steel pipe producers. What is more, the addition of more nickel in steel pipe coating will further increase the corrosion resistance of API 5l steel pipe. In particular, the API steel pipe resistance to pitting corrosion will be on the increase as long as nitrogen increases. Due to this reason, the mechanical strength of API steel pipe will be enhanced along with the resistance to pitting. In fact, steel pipe coating in use is in accordance with the metal cycles. Tens of thousands of workers rely on the steel pipe coating industry to support their lives. In some cases, API steel pipe is considered as a source for future secondary metal resources.
