316 stainless steel square tubes can be used in roadside guardrails, lamp poles, doors and windows, furniture, and marine equipment. They have excellent corrosion resistance, atmospheric corrosion resistance, and high temperature strength, and can be used under harsh conditions. Although 316 stainless steel has strong corrosion resistance, in the final analysis, stainless steel is a piece of impurities, composed of a variety of alloy elements, so corrosion is difficult to avoid. Today I will tell you the reasons for the corrosion of 316 stainless steel square tubes:
Due to road construction and passing vehicles, dust, iron powder, etc. are adsorbed on the stainless steel pipe and then corroded and rusted. At this time, the stainless steel pipe appears "incidental corrosion and rust", which is mostly not serious.
Harmful components in the exhaust gas can also cause corrosion and rust of stainless steel pipes. In construction sites and areas with busy traffic, the surface layer of stainless steel pipes is easily seriously polluted by exhaust gas emissions, and sometimes the surface layer will show small spots of corrosion and rust. This is mostly caused by harmful components such as sulfur contained in the exhaust of cars, air conditioners, or factory exhaust.
The sea breeze in coastal areas, the salt and chloride ion content in the air are very high, coupled with the humid environment, the guardrails, doors and windows corrode very quickly. The condensed water between the attachments and the 316 stainless steel square tube connects the two into a micro-battery, triggering an electrochemical reaction, and the protective film is damaged, which is called electrochemical corrosion.
The above can be cleaned with a clean rag and neutral detergent or soapy water, and the rust can be directly wiped and cleaned, and then rinsed with clean water, being careful not to leave detergent on the surface. This level of corrosion and rust cleaning only needs to be cleaned in time, which is simple to prevent and effective, and the cleaning cost is very low.
However, if left alone, the rust will quickly form a mixture of iron hydroxide, iron oxide, iron sulfite, etc., and turn into a serious brown corrosion rust state. At this time, it is necessary to use common stainless steel welded pipes cleaning liquid or 15℅ dilution of nitric acid to deep clean it. However, some rust will not be solved, and it will corrode the surface layer of 316 stainless steel square tubes to some extent, or damage the stainless steel tube. At this time, use sandpaper or brush to polish and wipe gently, and finally clean it with cleaning liquid.
There is also a kind of corrosion for marine equipment and ship components. Long-term contact with chloride ions and sodium ions in seawater will form countless tiny galvanic cells on the surface of stainless steel, which will corrode a large area over time. This is also a more serious type of electrochemical corrosion. Generally, it can be prevented by sacrificing active metals and protecting stainless steel.
The above are the reasons for the corrosion of 316 stainless steel square tubes. Dust, iron powder, sulfur elements, water, salt, and chlorine in the air can cause corrosion of steel pipes, but this mild corrosion can be well avoided as long as it is cleaned and wiped in time. There are a large number of chloride ions and sodium ions in the ocean, which form multiple primary cells on the surface of the pipe, and the corrosion rate is very fast; active metals can be sacrificed for corrosion protection.
