Ask for help about the causes of cracks in steel plates
Thread Content
The jacketed chute is used in the alkali recovery boiler of the pulping plant. The molten slurry (mainly Na2CO3, Na2S and other sodium salts, 800-900°C) flows outside, and the water flows inside (50-60°C). After running for a period of time, transverse cracks appear on the steel plate (material 304). What is the cause of this?
This post was last edited by CHANGBAISHI on 2018-11-16 15:34. It is caused by uneven heating and uneven stress. There may be a water outage, resulting in uneven cooling. It should be an operating accident.
Generally speaking, it is caused by stress.
It has nothing to do with processing. There are transverse cracks in the picture, and there are also longitudinal cracks.
A-SCC is more likely to be alkali embrittlement. I agree with what was said above. If it is heated unevenly, thermal ratchet corrosion may occur. To confirm, you need to look at the metallography to see if it is an epitaxial corrosion morphology or a transgranular corrosion morphology. Make another judgment. Contamination by Cl- (or other halogens) is not impossible. Also check whether the grains are coarse? very important