repair of lamination of plates or dished head

[ma]

Hi everybody

can some body help me to solve the following problem:
our dished head manufacturer fabricated an stainlees steel
trorespherical head (ID: 5000 mm) by spinning machine we found a
lamination defect in the knuckle area outside of the acceptance
criteria (as per ASME 435 , 75 mm diameter) how can we repair it? is
that allowed as per ASME standard, which article/

many thanks in advance
MA100

[Nilesh Pathare]

Dear MA100,

1. Find our the area of lamination by UT exactly. Depth of the lamiantion shall be determined correctly.

2.Then excavate up to the required depth by grinding / cutting wheel. Start the grinding from outer edge of the lamination. When the grinder reach to the lamination air gap the edge will start blackened.

3.After removal of the metal up to lamiantion depth check with UT at outer pherifery of the excaveted area to check the extension / complete removal of defect.

4. Carry out the penetrant test on edge of excavated area to confirm the edge free from defect.

5. Get the repair procedure approved from your client with approved WPS. Carry out the repair by welding. If the Depth is more then after 5 mm build up you can carry out UT test from opposite side to confirm the bonding between the WM and Base metal. Reference shall be 1.6mm dia. SDH.

6. smooth ground the welded area.

7. Carry out the UT testing for bond /clad between the WM & BM from repaired side. Verify the required thickness.                  Reference shall be 1.6mm dia. SDH. for normal probe. Also carry out scanning with 45 degree angle probe at 2 directional (90 degree) to detect cracks. Reference shall be ASME notch.

8. Verify the surface cracks by Penetrant Testing.

9. Check Hardness of the welded area.

Close out this issue with one NCR and all relevant test reports.

 

I hope This will help you. Code expert members comments welcome & shall be considered.

Regards,

Nilesh Pathare.

--
Best Regards,

Nilesh Pathare

[SENTHILKUMAR SWAMINATHAN]

SA 435 talks about steel plates and alloy steel plates. Can you give the stainless steel plate specification? More over UT by 0 & 45 Deg not enough. Other angle probes reqd.   S.Senthilkumar --- On Mon, 9/11/09, Nilesh Pathare <patha...@gmail.com> wrote:

Yahoo! India has a new look. Take a sneak peek.