Is the chloride content controlled in the water used for water cooling after heat treatment of austenitic stainless steel pipes?
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The sensitivity of austenitic stainless steel to chloride ions is well known; for example, the chloride ion content in the water used for pressure testing should be kept below 50 ppm (or even 25 ppm for stricter requirements). I believe that, in theory, the chloride ion content in the water used for cooling austenitic stainless steel pipes after heat treatment should also be controlled. However, in reality, when the temperature of the water used for heat treatment cooling rises, it should be replaced, and a relatively large amount of water is also required... So what is actually done in practice?
No, the pressure test controls chloride content to prevent stress corrosion.
:Lol, it’s actually a stainless steel tube. . . . 9 out of 10 have no water pressure. . Don’t worry about the chloride issue. . .
For the previous project, stainless steel welded pipes of GC1 grade were used, with high requirements; the owner sent people to supervise the manufacturing process, and hydrostatic testing was definitely required. After all, it’s welded pipe, and after heat treatment rapid cooling with water is required. Then I suddenly thought about the water used for this cooling… I also believe that probably no manufacturer pays attention to this aspect; it’s already quite good if they can carry out the hydrostatic test properly and pay attention to the chloride content in the water used for that test.
TSG D0001-2009 specifies that the chloride content in stainless steel shall not exceed 50 ppm, while 50184 states that it must not exceed 25 ppm. According to the hierarchy of regulatory standards, industrial pipelines are still required to have a chloride content of no more than 25 ppm