Purpose of controlling chloride ion content during hydrostatic testing of austenitic stainless steel vessels
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This post was last edited by SDHZZXM on 2017-7-5 at 17:05. As the title suggests: During the hydrostatic testing of austenitic stainless steel vessels, GB/T150.4 requires control over the chloride ion content. What is the purpose of this?
Too high chloride levels can cause stress corrosion
This post was last edited by SDHZZXM on 2017-7-5 at 18:05. Is intergranular corrosion a concern?
25 mg/l is empirical data; it is generally believed that this concentration does not cause stress corrosion in stainless steel. Stainless steel equipment has cracked during hydrotesting due to water quality issues; therefore, it is necessary to control water quality to avoid disasters.
Preventing intergranular corrosion in austenitic stainless steels
It contradicts the view on the 2nd floor – does that mean the answer on the 2nd floor is incorrect?
The purpose is to prevent chloride stress corrosion. Taking into account the fact that the pressure testing time for ordinary containers is usually short, the new regulatory standards stipulate that if the water is drained completely immediately after the hydrostatic test, it is not necessary to control the chloride content.
Its main purpose is to prevent chloride stress corrosion.
Intergranular corrosion in stainless steel occurs due to low chromium content; at high temperatures, chromium carbide is formed. Chloride ions are generally associated with stress corrosion, I think