Ladies and Gentlemen,
     "distorted structure"! The question to me in that is very broad. You might talk to a AWS staff engineer with a FAX or e-mail before
(American Welding Society (AWS)
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Miami, FL 33126
305-443-7559 FAX
Fax: (305) 443-5951  Engineer FAX

305 / 800-443-9353 )

asking with more details. Without more details I would not guess at your inquiry  I hope this helpful.
Sincerely
Len Andersen
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