郑州通风管道河南加工厂

Cause:

不锈钢点蚀多发生在含有碘、氯、溴等水溶液环境中。产生不锈钢点蚀的原因是氯离子是活性阴离子，容易被吸附，挤走氧原子，和钝化膜中的阳离子反应生成可溶性的氯化物，破坏钝化膜，形成小孔，成点蚀诱因阶段，在该阶段形成闭塞电路，发生电流腐蚀现象。

The pitting of stainless steel occurs mostly in aqueous solutions, such as iodine, chlorine and bromine. Causes of pitting corrosion of stainless steel is chloride is the active anion, easily adsorbed, as oxygen atoms, cationic reaction and passivation film formation in soluble chlorides, destroying the passivation film, the formation of holes into pitting inducement stage, blocking circuit formed in the current stage, occurrence of corrosion phenomenon.

防范措施：

Preventive measures:

1、在已知可能发生点蚀的环境中选择恰当的不锈钢材质，实验表明钼元素（Mo）或锰元素（Mn）含量越高的不锈钢，抵抗点蚀的能力就越强；

1, choose the right stainless steel material in the environment where pitting is known. Experiments show that the higher the content of molybdenum or Mo is, the stronger the ability to resist pitting is. The higher the content of Mn is,

2、控制与不锈钢接触液体的酸碱度，氯化物浓度以及温度；

2. Control the acidity and alkalinity of the liquid with stainless steel, the concentration of chloride and the temperature.

3、阴极保护，阳极保护或者同时采取这两种保护措施[1]；

3, cathodic protection, anodic protection or the adoption of these two protective measures at the same time, [1];

4、尽可能使用质量更好的不锈钢，如316或316L，来提高不锈钢风管的耐点状腐蚀性能。

4. Better stainless steel, such as 316 or 316L, is used as much as possible to improve the resistance to pitting corrosion resistance of the stainless steel pipe.