Re: [MW:15000] Re:Crack in the shell with thickness of 82.6 mm After PWHT

Dear Haja M Before analising the cause following data is important i) What is the base material and its chemistry ii) Was the plate  tested by UT,MP on Weld edge before Welding iii)How the eqpt was loaded during PWHT , Does it have adequet movent facilty during PWHT due to expansion iv) What is the welding parameter used , and consumable chemistry, Does weld tested by UT before PWHT some time RT will not reveal CRack in the weld. iv) Does Eqpt have restraint joint near the seam v) Does the crack is longitudinal along the weld (In weld ) or in HAZ,Does it have transvers net work of crack   All such information is very essential to analyse, Only  the  cooling rate of such a small deviation will not cause such a long crack   Regards   Hegde P.B. --- On Tue, 31/7/12, haja jaindeen <mhmj2k@yahoo.com> wrote: From: haja jaindeen <mhmj2k@yahoo.com> Subject: [MW:14996] Re:Crack in the shell with thickness of 82.6 mm After PWHT To: "materials-welding@googlegroups.com" <materials-welding@googlegroups.com> Date: Tuesday, 31 July, 2012, 7:51 PM Dear Experts, A Ring of diameter 4 m ( 82.6 mm thickness welded with 25 mm thickness) had  crack to the length of  4 m on the welded area after PWHT. After analyzing the reasons , while doing PWHT at the time  cooling stage, temperature maintained was 86.7 degree instead of 80 degree Max.. Is this is the reason for the crack. Experts please clarify the reason and solutions.Awaiting the response at the earliest. Regards / Haja M. -- To post to this group, send email to materials-welding@googlegroups.com To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com For more options, visit this group's bolg at http://materials-welding.blogspot.com/ The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.

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The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.