Is this caused by deformation of the tank wall or welding quality?
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This post was last edited by xuxu2018 on 2020-6-11 09:19. The factory started operating without conducting any tests after filling it with water; the medium used was also water. Then, after a few months of operation, a worker suddenly noticed that there seemed to be some deformation; it was not clear whether this deformation existed before filling with water or developed after operation began. We showed these photos to tank manufacturing plants with extensive construction experience to have them analyze the reasons. They said it was due to improper construction methods; from the photos, it seems that the cutting dimensions were not properly controlled during the production of the wall panels, and the verticality of the tank walls was not checked as required. Additionally, the shrinkage of the circumferential welds is significant. The tank can still be used, but closer monitoring is needed. Could everyone please take a look at this storage tank? In Figure 1, the wall plate of the bottom ring is tight at the upper end but loose at the lower end, resembling a flared shape ； Figure 2 shows that the circumferential weld appears tight here; indeed, there is hardly any verticality at all ； Figure 3 shows the entire tank; since the thickness of the tank walls decreases by 2 mm each time, it appears that the surface is uneven and wrinkled, not to mention the issue with its verticality. https://bbs.hcbbs.com/forum.php?mod=image&aid=2454673&size=300x300&key=cba8c3c0ec7a1e06&nocache=yes&type=fixnone
Just by looking at the pictures, it is obvious that the distortion of the tank is caused by the welding of steel plates. But perhaps it’s due to the shooting angle; since there are subsequent issues involved, such significant conclusions require on-site careful observation, comparison with design drawings, and measurement records before a cautious judgment can be made.
Yes, because I wasn’t at the scene, I only got photos. If the deformation is caused by foundation settlement or by the stress on the tank wall, is that the case?
Stainless steel welds tend to shrink, and this phenomenon probably occurs right after welding
I didn’t notice the black one; could you share your opinion?
It can’t even pass the inspection; it’s all crooked
No, no, I just happened to see a post at https://bbs.hcbbs.com/thread-3024669-1-1.html
Thank you for your advice. I see, I see :D At first, I only paid attention to the amount of weld contraction and didn’t notice the color; let’s check again to see whether the welding work meets the standards
Blackness of the weld is due to the lack of surface treatment after welding; unevenness at the weld site is a result of welding contraction (this phenomenon can be caused by incorrect dimensions of the tubular components being joined together, excessive welding current, etc.)
Thank you very much for your reply; I also learned a bit about the procedures for handling stainless steel welds. It is confirmed that the on-site construction team is unprofessional, and there are issues with the material cutting. What do we need to do if we decide to make corrections in this situation later on?